18681172 has 6 divisors (see below), whose sum is σ = 32692058. Its totient is φ = 9340584.

The previous prime is 18681167. The next prime is 18681197. The reversal of 18681172 is 27118681.

It can be written as a sum of positive squares in only one way, i.e., 13645636 + 5035536 = 3694^2 + 2244^2 .

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2335143 + ... + 2335150.

Almost surely, 2^18681172 is an apocalyptic number.

It is an amenable number.

18681172 is a deficient number, since it is larger than the sum of its proper divisors (14010886).

18681172 is a wasteful number, since it uses less digits than its factorization.

18681172 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4670297 (or 4670295 counting only the distinct ones).

The product of its digits is 5376, while the sum is 34.

The square root of 18681172 is about 4322.1721390986. The cubic root of 18681172 is about 265.3391741066.

The spelling of 18681172 in words is "eighteen million, six hundred eighty-one thousand, one hundred seventy-two".