18131886 has 24 divisors (see below), whose sum is σ = 39826800. Its totient is φ = 5960736.

The previous prime is 18131879. The next prime is 18131921. The reversal of 18131886 is 68813181.

18131886 = T₆₆₈ + T₆₆₉ + ... + T₇₄₀.

18131886 = 89² + 90² + ... + 380².

It is a self number, because there is not a number n which added to its sum of digits gives 18131886.

It is a congruent number.

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 5586 + ... + 8213.

It is an arithmetic number, because the mean of its divisors is an integer number (1659450).

Almost surely, 2^18131886 is an apocalyptic number.

18131886 is an abundant number, since it is smaller than the sum of its proper divisors (21694914).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18131886 is a wasteful number, since it uses less digits than its factorization.

18131886 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13880 (or 13877 counting only the distinct ones).

The product of its digits is 9216, while the sum is 36.

The square root of 18131886 is about 4258.1552343709. The cubic root of 18131886 is about 262.7126548897.

The spelling of 18131886 in words is "eighteen million, one hundred thirty-one thousand, eight hundred eighty-six".