18696881 has 6 divisors (see below), whose sum is σ = 21749490. Its totient is φ = 16025856.

The previous prime is 18696871. The next prime is 18696901. The reversal of 18696881 is 18869681.

It can be written as a sum of positive squares in only one way, i.e., 11621281 + 7075600 = 3409^2 + 2660^2 .

It is not a de Polignac number, because 18696881 - 2²² = 14502577 is a prime.

It is a super-2 number, since 2×18696881² = 699146718256322, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (18696841) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 190736 + ... + 190833.

It is an arithmetic number, because the mean of its divisors is an integer number (3624915).

Almost surely, 2^18696881 is an apocalyptic number.

It is an amenable number.

18696881 is a deficient number, since it is larger than the sum of its proper divisors (3052609).

18696881 is an equidigital number, since it uses as much as digits as its factorization.

18696881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 381583 (or 381576 counting only the distinct ones).

The product of its digits is 165888, while the sum is 47.

The square root of 18696881 is about 4323.9890147872. The cubic root of 18696881 is about 265.4135278514.

The spelling of 18696881 in words is "eighteen million, six hundred ninety-six thousand, eight hundred eighty-one".