18208222920 has 48 divisors (see below), whose sum is σ = 59176725660. Its totient is φ = 4855526016.

The previous prime is 18208222897. The next prime is 18208222931. The reversal of 18208222920 is 2922280281.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 16825721796 + 1382501124 = 129714^2 + 37182^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

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, 25288839 + ... + 25289558.

Almost surely, 2^18208222920 is an apocalyptic number.

18208222920 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18208222920 is an abundant number, since it is smaller than the sum of its proper divisors (40968502740).

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

18208222920 is a wasteful number, since it uses less digits than its factorization.

18208222920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50578414 (or 50578407 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 36.

The spelling of 18208222920 in words is "eighteen billion, two hundred eight million, two hundred twenty-two thousand, nine hundred twenty".