18981950625 has 135 divisors (see below), whose sum is σ = 37886741893. Its totient is φ = 9148260000.

The previous prime is 18981950599. The next prime is 18981950639. The reversal of 18981950625 is 52605918981.

The square root of 18981950625 is 137775.

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

18981950625 is a `hidden beast` number, since 1 + 8 + 9 + 8 + 1 + 9 + 5 + 0 + 625 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 1488184929 + 17493765696 = 38577^2 + 132264^2 .

It is not a de Polignac number, because 18981950625 - 2¹¹ = 18981948577 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 134 ways as a sum of consecutive naturals, for example, 113664292 + ... + 113664458.

Almost surely, 2^18981950625 is an apocalyptic number.

18981950625 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

18981950625 is the 137775-th square number.

18981950625 is the 68888-th centered octagonal number.

It is an amenable number.

18981950625 is a deficient number, since it is larger than the sum of its proper divisors (18904791268).

18981950625 is an equidigital number, since it uses as much as digits as its factorization.

18981950625 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 382 (or 186 counting only the distinct ones).

The product of its (nonzero) digits is 1555200, while the sum is 54.

The spelling of 18981950625 in words is "eighteen billion, nine hundred eighty-one million, nine hundred fifty thousand, six hundred twenty-five".