18310661 has 4 divisors (see below), whose sum is σ = 19274400. Its totient is φ = 17346924.

The previous prime is 18310651. The next prime is 18310673. The reversal of 18310661 is 16601381.

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 not a de Polignac number, because 18310661 - 2²² = 14116357 is a prime.

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 18310661.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18310651) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 481841 + ... + 481878.

It is an arithmetic number, because the mean of its divisors is an integer number (4818600).

Almost surely, 2^18310661 is an apocalyptic number.

It is an amenable number.

18310661 is a deficient number, since it is larger than the sum of its proper divisors (963739).

18310661 is an equidigital number, since it uses as much as digits as its factorization.

18310661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 963738.

The product of its (nonzero) digits is 864, while the sum is 26.

The square root of 18310661 is about 4279.0958157069. The cubic root of 18310661 is about 263.5732554996.

The spelling of 18310661 in words is "eighteen million, three hundred ten thousand, six hundred sixty-one".