18013919 has 24 divisors (see below), whose sum is σ = 24076800. Its totient is φ = 13290480.

The previous prime is 18013913. The next prime is 18013921. The reversal of 18013919 is 91931081.

It is a de Polignac number, because none of the positive numbers 2^k-18013919 is a prime.

It is a super-2 number, since 2×18013919² = 649002555477122, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18013913) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 9362 + ... + 11120.

It is an arithmetic number, because the mean of its divisors is an integer number (1003200).

Almost surely, 2^18013919 is an apocalyptic number.

18013919 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

18013919 is a deficient number, since it is larger than the sum of its proper divisors (6062881).

18013919 is a wasteful number, since it uses less digits than its factorization.

18013919 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1803 (or 1796 counting only the distinct ones).

The product of its (nonzero) digits is 1944, while the sum is 32.

The square root of 18013919 is about 4244.2807400077. The cubic root of 18013919 is about 262.1416740523.

The spelling of 18013919 in words is "eighteen million, thirteen thousand, nine hundred nineteen".