18624016321 has 2 divisors, whose sum is σ = 18624016322. Its totient is φ = 18624016320.

The previous prime is 18624016261. The next prime is 18624016339. The reversal of 18624016321 is 12361042681.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16961415696 + 1662600625 = 130236^2 + 40775^2 .

It is a cyclic number.

It is not a de Polignac number, because 18624016321 - 2²⁹ = 18087145409 is a prime.

It is not a weakly prime, because it can be changed into another prime (18624016381) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9312008160 + 9312008161.

It is an arithmetic number, because the mean of its divisors is an integer number (9312008161).

Almost surely, 2^18624016321 is an apocalyptic number.

It is an amenable number.

18624016321 is a deficient number, since it is larger than the sum of its proper divisors (1).

18624016321 is an equidigital number, since it uses as much as digits as its factorization.

18624016321 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 13824, while the sum is 34.

The spelling of 18624016321 in words is "eighteen billion, six hundred twenty-four million, sixteen thousand, three hundred twenty-one".