640155132 has 36 divisors (see below), whose sum is σ = 1624489776. Its totient is φ = 212551680.

The previous prime is 640155121. The next prime is 640155149. The reversal of 640155132 is 231551046.

640155132 is a `hidden beast` number, since 640 + 1 + 5 + 5 + 13 + 2 = 666.

It is a tau number, because it is divible by the number of its divisors (36).

It is a junction number, because it is equal to n+sod(n) for n = 640155096 and 640155105.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 25344 + ... + 43847.

It is an arithmetic number, because the mean of its divisors is an integer number (45124716).

Almost surely, 2^640155132 is an apocalyptic number.

It is an amenable number.

640155132 is an abundant number, since it is smaller than the sum of its proper divisors (984334644).

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

640155132 is a wasteful number, since it uses less digits than its factorization.

640155132 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 69458 (or 69453 counting only the distinct ones).

The product of its (nonzero) digits is 3600, while the sum is 27.

The square root of 640155132 is about 25301.2871609331. The cubic root of 640155132 is about 861.8434999214.

The spelling of 640155132 in words is "six hundred forty million, one hundred fifty-five thousand, one hundred thirty-two".