18885919 has 6 divisors (see below), whose sum is σ = 20450616. Its totient is φ = 17433000.

The previous prime is 18885907. The next prime is 18885961. The reversal of 18885919 is 91958881.

It is not a de Polignac number, because 18885919 - 2⁵ = 18885887 is a prime.

It is a super-2 number, since 2×18885919² = 713355872949122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18885019) by changing a digit.

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, 55707 + ... + 56044.

It is an arithmetic number, because the mean of its divisors is an integer number (3408436).

Almost surely, 2^18885919 is an apocalyptic number.

18885919 is a deficient number, since it is larger than the sum of its proper divisors (1564697).

18885919 is a wasteful number, since it uses less digits than its factorization.

18885919 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 111777 (or 111764 counting only the distinct ones).

The product of its digits is 207360, while the sum is 49.

The square root of 18885919 is about 4345.7932532508. The cubic root of 18885919 is about 266.3050328908.

The spelling of 18885919 in words is "eighteen million, eight hundred eighty-five thousand, nine hundred nineteen".