18311403444 has 24 divisors (see below), whose sum is σ = 44975377440. Its totient is φ = 5782548384.

The previous prime is 18311403437. The next prime is 18311403479. The reversal of 18311403444 is 44430411381.

It is a super-2 number, since 2×18311403444² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 40156359 + ... + 40156814.

It is an arithmetic number, because the mean of its divisors is an integer number (1873974060).

Almost surely, 2^18311403444 is an apocalyptic number.

It is an amenable number.

18311403444 is an abundant number, since it is smaller than the sum of its proper divisors (26663973996).

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

18311403444 is a wasteful number, since it uses less digits than its factorization.

18311403444 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80313199 (or 80313197 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 33.

The spelling of 18311403444 in words is "eighteen billion, three hundred eleven million, four hundred three thousand, four hundred forty-four".