645072132 has 12 divisors (see below), whose sum is σ = 1505168336. Its totient is φ = 215024040.

The previous prime is 645072119. The next prime is 645072163. The reversal of 645072132 is 231270546.

It is a tau number, because it is divible by the number of its divisors (12).

It is a super-2 number, since 2×645072132² = 832236110966050848, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 645072132.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 26877994 + ... + 26878017.

Almost surely, 2^645072132 is an apocalyptic number.

It is an amenable number.

645072132 is an abundant number, since it is smaller than the sum of its proper divisors (860096204).

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

645072132 is a wasteful number, since it uses less digits than its factorization.

645072132 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 53756018 (or 53756016 counting only the distinct ones).

The product of its (nonzero) digits is 10080, while the sum is 30.

The square root of 645072132 is about 25398.2702560627. The cubic root of 645072132 is about 864.0444668044.

The spelling of 645072132 in words is "six hundred forty-five million, seventy-two thousand, one hundred thirty-two".