256645332 has 18 divisors (see below), whose sum is σ = 648742458. Its totient is φ = 85548432.

The previous prime is 256645321. The next prime is 256645349. The reversal of 256645332 is 233546652.

256645332 is a `hidden beast` number, since 2 + 5 + 6 + 645 + 3 + 3 + 2 = 666.

It can be written as a sum of positive squares in only one way, i.e., 256448196 + 197136 = 16014^2 + 444^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a Harshad number since it is a multiple of its sum of digits (36), and also a Moran number because the ratio is a prime number: 7129037 = 256645332 / (2 + 5 + 6 + 6 + 4 + 5 + 3 + 3 + 2).

It is a congruent number.

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 5 ways as a sum of consecutive naturals, for example, 3564483 + ... + 3564554.

Almost surely, 2^256645332 is an apocalyptic number.

It is an amenable number.

256645332 is an abundant number, since it is smaller than the sum of its proper divisors (392097126).

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

256645332 is a wasteful number, since it uses less digits than its factorization.

256645332 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7129047 (or 7129042 counting only the distinct ones).

The product of its digits is 129600, while the sum is 36.

The square root of 256645332 is about 16020.1539318447. The cubic root of 256645332 is about 635.4935151205.

The spelling of 256645332 in words is "two hundred fifty-six million, six hundred forty-five thousand, three hundred thirty-two".