640354258 has 16 divisors (see below), whose sum is σ = 977722560. Its totient is φ = 314456976.

The previous prime is 640354243. The next prime is 640354279. The reversal of 640354258 is 852453046.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 180316 + ... + 183832.

It is an arithmetic number, because the mean of its divisors is an integer number (61107660).

Almost surely, 2^640354258 is an apocalyptic number.

640354258 is a deficient number, since it is larger than the sum of its proper divisors (337368302).

640354258 is a wasteful number, since it uses less digits than its factorization.

640354258 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5121.

The product of its (nonzero) digits is 115200, while the sum is 37.

The square root of 640354258 is about 25305.2219512100. The cubic root of 640354258 is about 861.9328520430.

The spelling of 640354258 in words is "six hundred forty million, three hundred fifty-four thousand, two hundred fifty-eight".