640090172 has 12 divisors (see below), whose sum is σ = 1120891800. Its totient is φ = 319835376.

The previous prime is 640090159. The next prime is 640090211. The reversal of 640090172 is 271090046.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 45458 + ... + 57849.

It is an arithmetic number, because the mean of its divisors is an integer number (93407650).

Almost surely, 2^640090172 is an apocalyptic number.

It is an amenable number.

640090172 is a deficient number, since it is larger than the sum of its proper divisors (480801628).

640090172 is a wasteful number, since it uses less digits than its factorization.

640090172 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 104860 (or 104858 counting only the distinct ones).

The product of its (nonzero) digits is 3024, while the sum is 29.

The square root of 640090172 is about 25300.0033992093. The cubic root of 640090172 is about 861.8143469631.

The spelling of 640090172 in words is "six hundred forty million, ninety thousand, one hundred seventy-two".