645081332 has 12 divisors (see below), whose sum is σ = 1290162720. Its totient is φ = 276463416.

The previous prime is 645081329. The next prime is 645081343. The reversal of 645081332 is 233180546.

645081332 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

645081332 is an admirable number.

It is a super-2 number, since 2×645081332² = 832259849789788448, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11519282 + ... + 11519337.

It is an arithmetic number, because the mean of its divisors is an integer number (107513560).

Almost surely, 2^645081332 is an apocalyptic number.

It is an amenable number.

645081332 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

645081332 is a wasteful number, since it uses less digits than its factorization.

645081332 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23038630 (or 23038628 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 32.

The square root of 645081332 is about 25398.4513701131. The cubic root of 645081332 is about 864.0485744439.

The spelling of 645081332 in words is "six hundred forty-five million, eighty-one thousand, three hundred thirty-two".