20331018 has 12 divisors (see below), whose sum is σ = 44050578. Its totient is φ = 6777000.

The previous prime is 20330993. The next prime is 20331023. The reversal of 20331018 is 81013302.

It can be written as a sum of positive squares in only one way, i.e., 19158129 + 1172889 = 4377^2 + 1083^2 .

It is a Harshad number since it is a multiple of its sum of digits (18), and also a Moran number because the ratio is a prime number: 1129501 = 20331018 / (2 + 0 + 3 + 3 + 1 + 0 + 1 + 8).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 564733 + ... + 564768.

Almost surely, 2^20331018 is an apocalyptic number.

20331018 is an abundant number, since it is smaller than the sum of its proper divisors (23719560).

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

20331018 is a wasteful number, since it uses less digits than its factorization.

20331018 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1129509 (or 1129506 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

The square root of 20331018 is about 4508.9930139666. The cubic root of 20331018 is about 272.9311100981.

The spelling of 20331018 in words is "twenty million, three hundred thirty-one thousand, eighteen".