18464993 has 4 divisors (see below), whose sum is σ = 18501780. Its totient is φ = 18428208.

The previous prime is 18464989. The next prime is 18465001. The reversal of 18464993 is 39946481.

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

It can be written as a sum of positive squares in 2 ways, for example, as 15108769 + 3356224 = 3887^2 + 1832^2 .

It is a cyclic number.

It is not a de Polignac number, because 18464993 - 2² = 18464989 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (18464983) 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, 17630 + ... + 18647.

It is an arithmetic number, because the mean of its divisors is an integer number (4625445).

Almost surely, 2^18464993 is an apocalyptic number.

It is an amenable number.

18464993 is a deficient number, since it is larger than the sum of its proper divisors (36787).

18464993 is an equidigital number, since it uses as much as digits as its factorization.

18464993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36786.

The product of its digits is 186624, while the sum is 44.

The square root of 18464993 is about 4297.0912254687. The cubic root of 18464993 is about 264.3116966212.

The spelling of 18464993 in words is "eighteen million, four hundred sixty-four thousand, nine hundred ninety-three".