640155275 has 12 divisors (see below), whose sum is σ = 810683232. Its totient is φ = 501227040.

The previous prime is 640155149. The next prime is 640155293. The reversal of 640155275 is 572551046.

It is not a de Polignac number, because 640155275 - 2²⁴ = 623378059 is a prime.

It is a super-2 number, since 2×640155275² = 819597552220651250, which contains 22 as substring.

It is a Duffinian 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, 271232 + ... + 273581.

It is an arithmetic number, because the mean of its divisors is an integer number (67556936).

Almost surely, 2^640155275 is an apocalyptic number.

640155275 is a deficient number, since it is larger than the sum of its proper divisors (170527957).

640155275 is a wasteful number, since it uses less digits than its factorization.

640155275 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 544870 (or 544865 counting only the distinct ones).

The product of its (nonzero) digits is 42000, while the sum is 35.

The square root of 640155275 is about 25301.2899868762. The cubic root of 640155275 is about 861.8435640952.

The spelling of 640155275 in words is "six hundred forty million, one hundred fifty-five thousand, two hundred seventy-five".