18478881 has 32 divisors (see below), whose sum is σ = 29306880. Its totient is φ = 11467008.

The previous prime is 18478853. The next prime is 18478891. The reversal of 18478881 is 18887481.

It is not a de Polignac number, because 18478881 - 2⁷ = 18478753 is a prime.

It is a super-2 number, since 2×18478881² = 682938086024322, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18478891) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 58135 + ... + 58451.

It is an arithmetic number, because the mean of its divisors is an integer number (915840).

Almost surely, 2^18478881 is an apocalyptic number.

It is an amenable number.

18478881 is a deficient number, since it is larger than the sum of its proper divisors (10827999).

18478881 is a wasteful number, since it uses less digits than its factorization.

18478881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 470 (or 464 counting only the distinct ones).

The product of its digits is 114688, while the sum is 45.

The square root of 18478881 is about 4298.7068985917. The cubic root of 18478881 is about 264.3779452416.

The spelling of 18478881 in words is "eighteen million, four hundred seventy-eight thousand, eight hundred eighty-one".