647123608 has 8 divisors (see below), whose sum is σ = 1213356780. Its totient is φ = 323561800.

The previous prime is 647123597. The next prime is 647123621. The reversal of 647123608 is 806321746.

It is a tau number, because it is divible by the number of its divisors (8).

It is a hoax number, since the sum of its digits (37) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40445218 + ... + 40445233.

Almost surely, 2^647123608 is an apocalyptic number.

It is an amenable number.

647123608 is a deficient number, since it is larger than the sum of its proper divisors (566233172).

647123608 is a wasteful number, since it uses less digits than its factorization.

647123608 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80890457 (or 80890453 counting only the distinct ones).

The product of its (nonzero) digits is 48384, while the sum is 37.

The square root of 647123608 is about 25438.6243338747. The cubic root of 647123608 is about 864.9594501356.

The spelling of 647123608 in words is "six hundred forty-seven million, one hundred twenty-three thousand, six hundred eight".