18522881 has 4 divisors (see below), whose sum is σ = 19947732. Its totient is φ = 17098032.

The previous prime is 18522871. The next prime is 18522883. The reversal of 18522881 is 18822581.

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

It can be written as a sum of positive squares in 2 ways, for example, as 5856400 + 12666481 = 2420^2 + 3559^2 .

It is a cyclic number.

It is not a de Polignac number, because 18522881 - 2⁶ = 18522817 is a prime.

It is a super-2 number, since 2×18522881² = 686194241080322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18522883) 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, 712406 + ... + 712431.

It is an arithmetic number, because the mean of its divisors is an integer number (4986933).

Almost surely, 2^18522881 is an apocalyptic number.

It is an amenable number.

18522881 is a deficient number, since it is larger than the sum of its proper divisors (1424851).

18522881 is a wasteful number, since it uses less digits than its factorization.

18522881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1424850.

The product of its digits is 10240, while the sum is 35.

The square root of 18522881 is about 4303.8216738150. The cubic root of 18522881 is about 264.5876153866.

The spelling of 18522881 in words is "eighteen million, five hundred twenty-two thousand, eight hundred eighty-one".