665172025 has 36 divisors (see below), whose sum is σ = 955589632. Its totient is φ = 449910720.

The previous prime is 665172023. The next prime is 665172061. The reversal of 665172025 is 520271566.

It is not a de Polignac number, because 665172025 - 2¹ = 665172023 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665172023) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 3844839 + ... + 3845011.

Almost surely, 2^665172025 is an apocalyptic number.

It is an amenable number.

665172025 is a deficient number, since it is larger than the sum of its proper divisors (290417607).

665172025 is a wasteful number, since it uses less digits than its factorization.

665172025 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 490 (or 312 counting only the distinct ones).

The product of its (nonzero) digits is 25200, while the sum is 34.

The square root of 665172025 is about 25790.9291224647. The cubic root of 665172025 is about 872.9271313622.

The spelling of 665172025 in words is "six hundred sixty-five million, one hundred seventy-two thousand, twenty-five".