18157725 has 18 divisors (see below), whose sum is σ = 32522906. Its totient is φ = 9684000.

The previous prime is 18157703. The next prime is 18157759. The reversal of 18157725 is 52775181.

18157725 is a `hidden beast` number, since 1 + 81 + 577 + 2 + 5 = 666.

It can be written as a sum of positive squares in 3 ways, for example, as 2452356 + 15705369 = 1566^2 + 3963^2 .

It is not a de Polignac number, because 18157725 - 2¹⁰ = 18156701 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 18157725.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 40126 + ... + 40575.

Almost surely, 2^18157725 is an apocalyptic number.

18157725 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

18157725 is a deficient number, since it is larger than the sum of its proper divisors (14365181).

18157725 is a wasteful number, since it uses less digits than its factorization.

18157725 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80717 (or 80709 counting only the distinct ones).

The product of its digits is 19600, while the sum is 36.

The square root of 18157725 is about 4261.1882145711. The cubic root of 18157725 is about 262.8373892995.

The spelling of 18157725 in words is "eighteen million, one hundred fifty-seven thousand, seven hundred twenty-five".