21333312018 has 48 divisors (see below), whose sum is σ = 46427763096. Its totient is φ = 7079546880.

The previous prime is 21333312001. The next prime is 21333312029. The reversal of 21333312018 is 81021333312.

21333312018 is a `hidden beast` number, since 2 + 1 + 333 + 312 + 0 + 18 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 21267263889 + 66048129 = 145833^2 + 8127^2 .

It is a super-2 number, since 2×21333312018² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21333311982 and 21333312000.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 4301196 + ... + 4306152.

Almost surely, 2^21333312018 is an apocalyptic number.

21333312018 is an abundant number, since it is smaller than the sum of its proper divisors (25094451078).

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

21333312018 is a wasteful number, since it uses less digits than its factorization.

21333312018 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5979 (or 5976 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 27.

The spelling of 21333312018 in words is "twenty-one billion, three hundred thirty-three million, three hundred twelve thousand, eighteen".