663172065 has 24 divisors (see below), whose sum is σ = 1151535528. Its totient is φ = 353064960.

The previous prime is 663172063. The next prime is 663172073. The reversal of 663172065 is 560271366.

It can be written as a sum of positive squares in 4 ways, for example, as 240746256 + 422425809 = 15516^2 + 20553^2 .

It is not a de Polignac number, because 663172065 - 2¹ = 663172063 is a prime.

It is not an unprimeable number, because it can be changed into a prime (663172061) 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, 13195 + ... + 38735.

It is an arithmetic number, because the mean of its divisors is an integer number (47980647).

Almost surely, 2^663172065 is an apocalyptic number.

It is an amenable number.

663172065 is a deficient number, since it is larger than the sum of its proper divisors (488363463).

663172065 is a wasteful number, since it uses less digits than its factorization.

663172065 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26129 (or 26126 counting only the distinct ones).

The product of its (nonzero) digits is 45360, while the sum is 36.

The square root of 663172065 is about 25752.1273878490. The cubic root of 663172065 is about 872.0513819743.

The spelling of 663172065 in words is "six hundred sixty-three million, one hundred seventy-two thousand, sixty-five".