18616645 has 4 divisors (see below), whose sum is σ = 22339980. Its totient is φ = 14893312.

The previous prime is 18616627. The next prime is 18616657. The reversal of 18616645 is 54661681.

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 14092516 + 4524129 = 3754^2 + 2127^2 .

It is a cyclic number.

It is not a de Polignac number, because 18616645 - 2⁷ = 18616517 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1861660 + ... + 1861669.

It is an arithmetic number, because the mean of its divisors is an integer number (5584995).

Almost surely, 2^18616645 is an apocalyptic number.

It is an amenable number.

18616645 is a deficient number, since it is larger than the sum of its proper divisors (3723335).

18616645 is an equidigital number, since it uses as much as digits as its factorization.

18616645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3723334.

The product of its digits is 34560, while the sum is 37.

The square root of 18616645 is about 4314.7010325166. The cubic root of 18616645 is about 265.0333172777.

The spelling of 18616645 in words is "eighteen million, six hundred sixteen thousand, six hundred forty-five".