640252366 has 32 divisors (see below), whose sum is σ = 1065808800. Its totient is φ = 286540416.

The previous prime is 640252313. The next prime is 640252373. The reversal of 640252366 is 663252046.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 334785 + ... + 336691.

It is an arithmetic number, because the mean of its divisors is an integer number (33306525).

Almost surely, 2^640252366 is an apocalyptic number.

640252366 is a deficient number, since it is larger than the sum of its proper divisors (425556434).

640252366 is a wasteful number, since it uses less digits than its factorization.

640252366 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2308.

The product of its (nonzero) digits is 51840, while the sum is 34.

The square root of 640252366 is about 25303.2086107671. The cubic root of 640252366 is about 861.8871332243.

The spelling of 640252366 in words is "six hundred forty million, two hundred fifty-two thousand, three hundred sixty-six".