18211910400 has 810 divisors, whose sum is σ = 72568571460. Its totient is φ = 4493905920.

The previous prime is 18211910359. The next prime is 18211910429. The reversal of 18211910400 is 401911281.

It is a tau number, because it is divible by the number of its divisors (810).

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an unprimeable number.

It is a polite number, since it can be written in 89 ways as a sum of consecutive naturals, for example, 423532779 + ... + 423532821.

Almost surely, 2^18211910400 is an apocalyptic number.

18211910400 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18211910400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36284285730).

18211910400 is an abundant number, since it is smaller than the sum of its proper divisors (54356661060).

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

18211910400 is an equidigital number, since it uses as much as digits as its factorization.

18211910400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 143 (or 72 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 27.

The spelling of 18211910400 in words is "eighteen billion, two hundred eleven million, nine hundred ten thousand, four hundred".