18243663400 has 48 divisors (see below), whose sum is σ = 43451086140. Its totient is φ = 7119475200.

The previous prime is 18243663391. The next prime is 18243663421. The reversal of 18243663400 is 436634281.

It can be written as a sum of positive squares in 6 ways, for example, as 6991969924 + 11251693476 = 83618^2 + 106074^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 18243663400.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1104219 + ... + 1120618.

Almost surely, 2^18243663400 is an apocalyptic number.

18243663400 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18243663400 is an abundant number, since it is smaller than the sum of its proper divisors (25207422740).

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

18243663400 is a wasteful number, since it uses less digits than its factorization.

18243663400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2224894 (or 2224885 counting only the distinct ones).

The product of its (nonzero) digits is 82944, while the sum is 37.

The spelling of 18243663400 in words is "eighteen billion, two hundred forty-three million, six hundred sixty-three thousand, four hundred".