18376981 has 8 divisors (see below), whose sum is σ = 21726720. Its totient is φ = 15208368.

The previous prime is 18376957. The next prime is 18376991. The reversal of 18376981 is 18967381.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 18376981 - 2¹¹ = 18374933 is a prime.

It is a super-2 number, since 2×18376981² = 675426861348722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18376991) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 45061 + ... + 45466.

It is an arithmetic number, because the mean of its divisors is an integer number (2715840).

Almost surely, 2^18376981 is an apocalyptic number.

It is an amenable number.

18376981 is a deficient number, since it is larger than the sum of its proper divisors (3349739).

18376981 is an equidigital number, since it uses as much as digits as its factorization.

18376981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 90563.

The product of its digits is 72576, while the sum is 43.

The square root of 18376981 is about 4286.8381121755. The cubic root of 18376981 is about 263.8910870378.

The spelling of 18376981 in words is "eighteen million, three hundred seventy-six thousand, nine hundred eighty-one".