18999226656 has 72 divisors (see below), whose sum is σ = 57207245004. Its totient is φ = 5960540160.

The previous prime is 18999226621. The next prime is 18999226679. The reversal of 18999226656 is 65662299981.

It can be written as a sum of positive squares in 2 ways, for example, as 14472090000 + 4527136656 = 120300^2 + 67284^2 .

It is a tau number, because it is divible by the number of its divisors (72).

It is a super-2 number, since 2×18999226656² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 18999226593 and 18999226602.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1935385 + ... + 1945176.

Almost surely, 2^18999226656 is an apocalyptic number.

18999226656 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

18999226656 is an abundant number, since it is smaller than the sum of its proper divisors (38208018348).

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

18999226656 is a wasteful number, since it uses less digits than its factorization.

18999226656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3880594 (or 3880583 counting only the distinct ones).

The product of its digits is 25194240, while the sum is 63.

The spelling of 18999226656 in words is "eighteen billion, nine hundred ninety-nine million, two hundred twenty-six thousand, six hundred fifty-six".