18212110191920 has 40 divisors (see below), whose sum is σ = 42349554641040. Its totient is φ = 7283743269120.

The previous prime is 18212110191901. The next prime is 18212110191923. The reversal of 18212110191920 is 2919101121281.

It is a tau number, because it is divible by the number of its divisors (40).

It is not an unprimeable number, because it can be changed into a prime (18212110191923) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16667291 + ... + 17726330.

It is an arithmetic number, because the mean of its divisors is an integer number (1058738866026).

Almost surely, 2^{18212110191920} is an apocalyptic number.

18212110191920 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18212110191920 is an abundant number, since it is smaller than the sum of its proper divisors (24137444449120).

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

18212110191920 is a wasteful number, since it uses less digits than its factorization.

18212110191920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34400253 (or 34400247 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 38.

The spelling of 18212110191920 in words is "eighteen trillion, two hundred twelve billion, one hundred ten million, one hundred ninety-one thousand, nine hundred twenty".