18628305661 has 8 divisors (see below), whose sum is σ = 21294114624. Its totient is φ = 15963652320.

The previous prime is 18628305617. The next prime is 18628305739. The reversal of 18628305661 is 16650382681.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 18628305661 - 2⁷ = 18628305533 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18628305601) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 254080 + ... + 319081.

It is an arithmetic number, because the mean of its divisors is an integer number (2661764328).

Almost surely, 2^18628305661 is an apocalyptic number.

It is an amenable number.

18628305661 is a deficient number, since it is larger than the sum of its proper divisors (2665808963).

18628305661 is an equidigital number, since it uses as much as digits as its factorization.

18628305661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 577811.

The product of its (nonzero) digits is 414720, while the sum is 46.

The spelling of 18628305661 in words is "eighteen billion, six hundred twenty-eight million, three hundred five thousand, six hundred sixty-one".