18211858572 has 12 divisors (see below), whose sum is σ = 42494336696. Its totient is φ = 6070619520.

The previous prime is 18211858559. The next prime is 18211858601. The reversal of 18211858572 is 27585811281.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (12).

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 758827429 + ... + 758827452.

Almost surely, 2^18211858572 is an apocalyptic number.

18211858572 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

18211858572 is an abundant number, since it is smaller than the sum of its proper divisors (24282478124).

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

18211858572 is a wasteful number, since it uses less digits than its factorization.

18211858572 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1517654888 (or 1517654886 counting only the distinct ones).

The product of its digits is 358400, while the sum is 48.

The spelling of 18211858572 in words is "eighteen billion, two hundred eleven million, eight hundred fifty-eight thousand, five hundred seventy-two".