18122531 has 8 divisors (see below), whose sum is σ = 20917344. Its totient is φ = 15379200.

The previous prime is 18122509. The next prime is 18122539. The reversal of 18122531 is 13522181.

It is a happy number.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18122531 is a prime.

It is a super-2 number, since 2×18122531² = 656852259691922, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 18122497 and 18122506.

It is not an unprimeable number, because it can be changed into a prime (18122539) 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, 12110 + ... + 13523.

It is an arithmetic number, because the mean of its divisors is an integer number (2614668).

Almost surely, 2^18122531 is an apocalyptic number.

18122531 is a deficient number, since it is larger than the sum of its proper divisors (2794813).

18122531 is a wasteful number, since it uses less digits than its factorization.

18122531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25741.

The product of its digits is 480, while the sum is 23.

The square root of 18122531 is about 4257.0566122616. The cubic root of 18122531 is about 262.6674656270.

The spelling of 18122531 in words is "eighteen million, one hundred twenty-two thousand, five hundred thirty-one".