647142657 has 24 divisors (see below), whose sum is σ = 1009573056. Its totient is φ = 367643808.

The previous prime is 647142649. The next prime is 647142709. The reversal of 647142657 is 756241746.

It is not a de Polignac number, because 647142657 - 2³ = 647142649 is a prime.

It is not an unprimeable number, because it can be changed into a prime (647142607) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 12708 + ... + 38154.

It is an arithmetic number, because the mean of its divisors is an integer number (42065544).

Almost surely, 2^647142657 is an apocalyptic number.

It is an amenable number.

647142657 is a deficient number, since it is larger than the sum of its proper divisors (362430399).

647142657 is a wasteful number, since it uses less digits than its factorization.

647142657 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25637 (or 25630 counting only the distinct ones).

The product of its digits is 282240, while the sum is 42.

The square root of 647142657 is about 25438.9987420889. The cubic root of 647142657 is about 864.9679371545.

The spelling of 647142657 in words is "six hundred forty-seven million, one hundred forty-two thousand, six hundred fifty-seven".