18919153 has 4 divisors (see below), whose sum is σ = 20639088. Its totient is φ = 17199220.

The previous prime is 18919141. The next prime is 18919169. The reversal of 18919153 is 35191981.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18919153 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18914153) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 859951 + ... + 859972.

It is an arithmetic number, because the mean of its divisors is an integer number (5159772).

Almost surely, 2^18919153 is an apocalyptic number.

It is an amenable number.

18919153 is a deficient number, since it is larger than the sum of its proper divisors (1719935).

18919153 is a wasteful number, since it uses less digits than its factorization.

18919153 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1719934.

The product of its digits is 9720, while the sum is 37.

The square root of 18919153 is about 4349.6152703429. The cubic root of 18919153 is about 266.4611491155.

The spelling of 18919153 in words is "eighteen million, nine hundred nineteen thousand, one hundred fifty-three".