664350625 has 15 divisors (see below), whose sum is σ = 830978533. Its totient is φ = 530965000.

The previous prime is 664350613. The next prime is 664350641. The reversal of 664350625 is 526053466.

The square root of 664350625 is 25775.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 2 ways, for example, as 52085089 + 612265536 = 7217^2 + 24744^2 .

It is not a de Polignac number, because 664350625 - 2¹¹ = 664348577 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 14 ways as a sum of consecutive naturals, for example, 643860 + ... + 644890.

Almost surely, 2^664350625 is an apocalyptic number.

664350625 is the 25775-th square number.

664350625 is the 12888-th centered octagonal number.

It is an amenable number.

664350625 is a deficient number, since it is larger than the sum of its proper divisors (166627908).

664350625 is an frugal number, since it uses more digits than its factorization.

664350625 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2082 (or 1036 counting only the distinct ones).

The product of its (nonzero) digits is 129600, while the sum is 37.

The cubic root of 664350625 is about 872.5676666102.

Multiplying 664350625 by its product of nonzero digits (129600), we get a square (86099841000000 = 9279000²).

The spelling of 664350625 in words is "six hundred sixty-four million, three hundred fifty thousand, six hundred twenty-five".