18634561825 has 12 divisors (see below), whose sum is σ = 25207480368. Its totient is φ = 13552408400.

The previous prime is 18634561817. The next prime is 18634561837. The reversal of 18634561825 is 52816543681.

It is not a de Polignac number, because 18634561825 - 2³ = 18634561817 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 33880747 + ... + 33881296.

It is an arithmetic number, because the mean of its divisors is an integer number (2100623364).

Almost surely, 2^18634561825 is an apocalyptic number.

It is an amenable number.

18634561825 is a deficient number, since it is larger than the sum of its proper divisors (6572918543).

18634561825 is a wasteful number, since it uses less digits than its factorization.

18634561825 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 67762064 (or 67762059 counting only the distinct ones).

The product of its digits is 1382400, while the sum is 49.

The spelling of 18634561825 in words is "eighteen billion, six hundred thirty-four million, five hundred sixty-one thousand, eight hundred twenty-five".