617639664 has 20 divisors (see below), whose sum is σ = 1595569256. Its totient is φ = 205879872.

The previous prime is 617639657. The next prime is 617639731. The reversal of 617639664 is 466936716.

It is a Harshad number since it is a multiple of its sum of digits (48), and also a Moran number because the ratio is a prime number: 12867493 = 617639664 / (6 + 1 + 7 + 6 + 3 + 9 + 6 + 6 + 4).

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, 6433699 + ... + 6433794.

Almost surely, 2^617639664 is an apocalyptic number.

It is an amenable number.

617639664 is an abundant number, since it is smaller than the sum of its proper divisors (977929592).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

617639664 is a wasteful number, since it uses less digits than its factorization.

617639664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12867504 (or 12867498 counting only the distinct ones).

The product of its digits is 979776, while the sum is 48.

The square root of 617639664 is about 24852.3573127380. The cubic root of 617639664 is about 851.6184453881.

The spelling of 617639664 in words is "six hundred seventeen million, six hundred thirty-nine thousand, six hundred sixty-four".