18457919 has 4 divisors (see below), whose sum is σ = 18506496. Its totient is φ = 18409344.

The previous prime is 18457883. The next prime is 18457969. The reversal of 18457919 is 91975481.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 18457919 - 2¹⁶ = 18392383 is a prime.

It is a super-2 number, since 2×18457919² = 681389547621122, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 18457919.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18457969) 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, 23714 + ... + 24479.

It is an arithmetic number, because the mean of its divisors is an integer number (4626624).

Almost surely, 2^18457919 is an apocalyptic number.

18457919 is a deficient number, since it is larger than the sum of its proper divisors (48577).

18457919 is an equidigital number, since it uses as much as digits as its factorization.

18457919 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 48576.

The product of its digits is 90720, while the sum is 44.

The square root of 18457919 is about 4296.2680316759. The cubic root of 18457919 is about 264.2779394144.

The spelling of 18457919 in words is "eighteen million, four hundred fifty-seven thousand, nine hundred nineteen".