1264489380 has 576 divisors, whose sum is σ = 5166120960. Its totient is φ = 251942400.

The previous prime is 1264489379. The next prime is 1264489399. The reversal of 1264489380 is 839844621.

It is a happy number.

1264489380 is a `hidden beast` number, since 1 + 264 + 4 + 8 + 9 + 380 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 11600766 + ... + 11600874.

It is an arithmetic number, because the mean of its divisors is an integer number (8968960).

Almost surely, 2^1264489380 is an apocalyptic number.

1264489380 is a gapful number since it is divisible by the number (10) 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 1264489380, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2583060480).

1264489380 is an abundant number, since it is smaller than the sum of its proper divisors (3901631580).

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

1264489380 is a wasteful number, since it uses less digits than its factorization.

1264489380 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 182 (or 168 counting only the distinct ones).

The product of its (nonzero) digits is 331776, while the sum is 45.

The square root of 1264489380 is about 35559.6594471882. The cubic root of 1264489380 is about 1081.3635554944.

It can be divided in two parts, 126 and 4489380, that added together give a triangular number (4489506 = T₂₉₉₆).

The spelling of 1264489380 in words is "one billion, two hundred sixty-four million, four hundred eighty-nine thousand, three hundred eighty".