1264877640 has 256 divisors, whose sum is σ = 4739212800. Its totient is φ = 297741312.

The previous prime is 1264877629. The next prime is 1264877683. The reversal of 1264877640 is 467784621.

1264877640 is a `hidden beast` number, since 126 + 487 + 7 + 6 + 40 = 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 63 ways as a sum of consecutive naturals, for example, 320962 + ... + 324878.

It is an arithmetic number, because the mean of its divisors is an integer number (18512550).

Almost surely, 2^1264877640 is an apocalyptic number.

1264877640 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 1264877640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2369606400).

1264877640 is an abundant number, since it is smaller than the sum of its proper divisors (3474335160).

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

1264877640 is a wasteful number, since it uses less digits than its factorization.

1264877640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3973 (or 3963 counting only the distinct ones).

The product of its (nonzero) digits is 451584, while the sum is 45.

The square root of 1264877640 is about 35565.1183043161. The cubic root of 1264877640 is about 1081.4742213111.

The spelling of 1264877640 in words is "one billion, two hundred sixty-four million, eight hundred seventy-seven thousand, six hundred forty".