640354810 has 32 divisors (see below), whose sum is σ = 1250221392. Its totient is φ = 235192320.

The previous prime is 640354807. The next prime is 640354823. The reversal of 640354810 is 18453046.

It is a happy number.

640354810 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 8 ways, for example, as 421521961 + 218832849 = 20531^2 + 14793^2 .

It is a super-2 number, since 2×640354810² = 820108565380272200, which contains 22 as substring.

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, 38967 + ... + 52906.

Almost surely, 2^640354810 is an apocalyptic number.

640354810 is a deficient number, since it is larger than the sum of its proper divisors (609866582).

640354810 is a wasteful number, since it uses less digits than its factorization.

640354810 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 91938.

The product of its (nonzero) digits is 11520, while the sum is 31.

The square root of 640354810 is about 25305.2328580474. The cubic root of 640354810 is about 861.9330997116.

The spelling of 640354810 in words is "six hundred forty million, three hundred fifty-four thousand, eight hundred ten".