640626422 has 8 divisors (see below), whose sum is σ = 970269456. Its totient is φ = 317203272.

The previous prime is 640626407. The next prime is 640626431. The reversal of 640626422 is 224626046.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1554713 + ... + 1555124.

It is an arithmetic number, because the mean of its divisors is an integer number (121283682).

Almost surely, 2^640626422 is an apocalyptic number.

640626422 is a deficient number, since it is larger than the sum of its proper divisors (329643034).

640626422 is a wasteful number, since it uses less digits than its factorization.

640626422 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3109942.

The product of its (nonzero) digits is 27648, while the sum is 32.

The square root of 640626422 is about 25310.5990051599. The cubic root of 640626422 is about 862.0549479313.

The spelling of 640626422 in words is "six hundred forty million, six hundred twenty-six thousand, four hundred twenty-two".