1261469664 has 288 divisors, whose sum is σ = 4461649920. Its totient is φ = 329204736.

The previous prime is 1261469659. The next prime is 1261469669. The reversal of 1261469664 is 4669641621.

It is a happy number.

1261469664 is a `hidden beast` number, since 126 + 1 + 469 + 6 + 64 = 666.

It is an interprime number because it is at equal distance from previous prime (1261469659) and next prime (1261469669).

It is a tau number, because it is divible by the number of its divisors (288).

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1261469669) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 3328227 + ... + 3328605.

It is an arithmetic number, because the mean of its divisors is an integer number (15491840).

Almost surely, 2^1261469664 is an apocalyptic number.

1261469664 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1261469664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2230824960).

1261469664 is an abundant number, since it is smaller than the sum of its proper divisors (3200180256).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1261469664 is a wasteful number, since it uses less digits than its factorization.

1261469664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 542 (or 531 counting only the distinct ones).

The product of its digits is 373248, while the sum is 45.

The square root of 1261469664 is about 35517.1742119218. The cubic root of 1261469664 is about 1080.5020710875.

It can be divided in two parts, 126 and 1469664, that multiplied together give a square (185177664 = 13608²).

The spelling of 1261469664 in words is "one billion, two hundred sixty-one million, four hundred sixty-nine thousand, six hundred sixty-four".