647640165 has 16 divisors (see below), whose sum is σ = 1038296448. Its totient is φ = 344717376.

The previous prime is 647640163. The next prime is 647640173. The reversal of 647640165 is 561046746.

It is not a de Polignac number, because 647640165 - 2¹ = 647640163 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (647640163) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 35374 + ... + 50463.

It is an arithmetic number, because the mean of its divisors is an integer number (64893528).

Almost surely, 2^647640165 is an apocalyptic number.

It is an amenable number.

647640165 is a deficient number, since it is larger than the sum of its proper divisors (390656283).

647640165 is a wasteful number, since it uses less digits than its factorization.

647640165 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 86348.

The product of its (nonzero) digits is 120960, while the sum is 39.

The square root of 647640165 is about 25448.7753143447. The cubic root of 647640165 is about 865.1895360222.

The spelling of 647640165 in words is "six hundred forty-seven million, six hundred forty thousand, one hundred sixty-five".