18215321131 has 8 divisors (see below), whose sum is σ = 21102681824. Its totient is φ = 15399253440.

The previous prime is 18215321107. The next prime is 18215321153. The reversal of 18215321131 is 13112351281.

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

It is a cyclic number.

It is not a de Polignac number, because 18215321131 - 2⁵ = 18215321099 is a prime.

It is a super-2 number, since 2×18215321131² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 18215321131.

It is not an unprimeable number, because it can be changed into a prime (18215321171) 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, 17822700 + ... + 17823721.

It is an arithmetic number, because the mean of its divisors is an integer number (2637835228).

Almost surely, 2^18215321131 is an apocalyptic number.

18215321131 is a deficient number, since it is larger than the sum of its proper divisors (2887360693).

18215321131 is an equidigital number, since it uses as much as digits as its factorization.

18215321131 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35646501.

The product of its digits is 1440, while the sum is 28.

The spelling of 18215321131 in words is "eighteen billion, two hundred fifteen million, three hundred twenty-one thousand, one hundred thirty-one".