1264156880 has 120 divisors (see below), whose sum is σ = 3438483048. Its totient is φ = 430961664.

The previous prime is 1264156819. The next prime is 1264156903. The reversal of 1264156880 is 886514621.

It can be written as a sum of positive squares in 4 ways, for example, as 138956944 + 1125199936 = 11788^2 + 33544^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 771422 + ... + 773058.

Almost surely, 2^1264156880 is an apocalyptic number.

1264156880 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 1264156880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1719241524).

1264156880 is an abundant number, since it is smaller than the sum of its proper divisors (2174326168).

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

1264156880 is a wasteful number, since it uses less digits than its factorization.

1264156880 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1861 (or 1848 counting only the distinct ones).

The product of its (nonzero) digits is 92160, while the sum is 41.

The square root of 1264156880 is about 35554.9838981823. The cubic root of 1264156880 is about 1081.2687649522.

The spelling of 1264156880 in words is "one billion, two hundred sixty-four million, one hundred fifty-six thousand, eight hundred eighty".