660172025 has 6 divisors (see below), whose sum is σ = 818613342. Its totient is φ = 528137600.

The previous prime is 660171997. The next prime is 660172087. The reversal of 660172025 is 520271066.

It can be written as a sum of positive squares in 3 ways, for example, as 61293241 + 598878784 = 7829^2 + 24472^2 .

It is not a de Polignac number, because 660172025 - 2⁸ = 660171769 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 13203416 + ... + 13203465.

It is an arithmetic number, because the mean of its divisors is an integer number (136435557).

Almost surely, 2^660172025 is an apocalyptic number.

It is an amenable number.

660172025 is a deficient number, since it is larger than the sum of its proper divisors (158441317).

660172025 is a wasteful number, since it uses less digits than its factorization.

660172025 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26406891 (or 26406886 counting only the distinct ones).

The product of its (nonzero) digits is 5040, while the sum is 29.

The square root of 660172025 is about 25693.8129712194. The cubic root of 660172025 is about 870.7344065234.

The spelling of 660172025 in words is "six hundred sixty million, one hundred seventy-two thousand, twenty-five".