1265656660 has 48 divisors (see below), whose sum is σ = 2688940800. Its totient is φ = 500382080.

The previous prime is 1265656603. The next prime is 1265656697. The reversal of 1265656660 is 666565621.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 675525 + ... + 677395.

It is an arithmetic number, because the mean of its divisors is an integer number (56019600).

Almost surely, 2^1265656660 is an apocalyptic number.

1265656660 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1265656660 is an abundant number, since it is smaller than the sum of its proper divisors (1423284140).

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

1265656660 is a wasteful number, since it uses less digits than its factorization.

1265656660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2256 (or 2254 counting only the distinct ones).

The product of its (nonzero) digits is 388800, while the sum is 43.

The square root of 1265656660 is about 35576.0686417148. The cubic root of 1265656660 is about 1081.6961972349.

It can be divided in two parts, 126565 and 6660, that added together give a square (133225 = 365²).

The spelling of 1265656660 in words is "one billion, two hundred sixty-five million, six hundred fifty-six thousand, six hundred sixty".