646515697 has 4 divisors (see below), whose sum is σ = 654699520. Its totient is φ = 638331876.

The previous prime is 646515643. The next prime is 646515703. The reversal of 646515697 is 796515646.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 646515697 - 2¹⁵ = 646482929 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 646515697.

It is not an unprimeable number, because it can be changed into a prime (646515607) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4091793 + ... + 4091950.

It is an arithmetic number, because the mean of its divisors is an integer number (163674880).

Almost surely, 2^646515697 is an apocalyptic number.

It is an amenable number.

646515697 is a deficient number, since it is larger than the sum of its proper divisors (8183823).

646515697 is an equidigital number, since it uses as much as digits as its factorization.

646515697 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8183822.

The product of its digits is 1360800, while the sum is 49.

The square root of 646515697 is about 25426.6729439776. The cubic root of 646515697 is about 864.6885162698.

The spelling of 646515697 in words is "six hundred forty-six million, five hundred fifteen thousand, six hundred ninety-seven".