19902018 has 16 divisors (see below), whose sum is σ = 39911040. Its totient is φ = 6616176.

The previous prime is 19902017. The next prime is 19902023. The reversal of 19902018 is 81020991.

It is not an unprimeable number, because it can be changed into a prime (19902011) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 1930 + ... + 6597.

It is an arithmetic number, because the mean of its divisors is an integer number (2494440).

Almost surely, 2^19902018 is an apocalyptic number.

19902018 is an abundant number, since it is smaller than the sum of its proper divisors (20009022).

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

19902018 is a wasteful number, since it uses less digits than its factorization.

19902018 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8921.

The product of its (nonzero) digits is 1296, while the sum is 30.

The square root of 19902018 is about 4461.1677843363. The cubic root of 19902018 is about 270.9977623577.

The spelling of 19902018 in words is "nineteen million, nine hundred two thousand, eighteen".