264788640 has 72 divisors (see below), whose sum is σ = 903596148. Its totient is φ = 70609920.

The previous prime is 264788621. The next prime is 264788653. The reversal of 264788640 is 46887462.

It can be written as a sum of positive squares in 2 ways, for example, as 237036816 + 27751824 = 15396^2 + 5268^2 .

It is a tau number, because it is divible by the number of its divisors (72).

It is a super-2 number, since 2×264788640² = 140226047746099200, which contains 22 as substring.

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 90501 + ... + 93380.

Almost surely, 2^264788640 is an apocalyptic number.

264788640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

264788640 is an abundant number, since it is smaller than the sum of its proper divisors (638807508).

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

264788640 is a wasteful number, since it uses less digits than its factorization.

264788640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 183902 (or 183891 counting only the distinct ones).

The product of its (nonzero) digits is 516096, while the sum is 45.

The square root of 264788640 is about 16272.3274303340. The cubic root of 264788640 is about 642.1450162991.

The spelling of 264788640 in words is "two hundred sixty-four million, seven hundred eighty-eight thousand, six hundred forty".