18881131 has 4 divisors (see below), whose sum is σ = 19008000. Its totient is φ = 18754264.

The previous prime is 18881129. The next prime is 18881141. The reversal of 18881131 is 13118881.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 18881131 - 2¹ = 18881129 is a prime.

It is a super-2 number, since 2×18881131² = 712994215678322, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 18881093 and 18881102.

It is not an unprimeable number, because it can be changed into a prime (18881141) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 63211 + ... + 63508.

It is an arithmetic number, because the mean of its divisors is an integer number (4752000).

Almost surely, 2^18881131 is an apocalyptic number.

18881131 is a deficient number, since it is larger than the sum of its proper divisors (126869).

18881131 is a wasteful number, since it uses less digits than its factorization.

18881131 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 126868.

The product of its digits is 1536, while the sum is 31.

The square root of 18881131 is about 4345.2423407677. The cubic root of 18881131 is about 266.2825262415.

The spelling of 18881131 in words is "eighteen million, eight hundred eighty-one thousand, one hundred thirty-one".