18909625 has 16 divisors (see below), whose sum is σ = 26971776. Its totient is φ = 12966000.

The previous prime is 18909623. The next prime is 18909629. The reversal of 18909625 is 52690981.

It is not a de Polignac number, because 18909625 - 2¹ = 18909623 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18909623) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9931 + ... + 11680.

It is an arithmetic number, because the mean of its divisors is an integer number (1685736).

Almost surely, 2^18909625 is an apocalyptic number.

It is an amenable number.

18909625 is a deficient number, since it is larger than the sum of its proper divisors (8062151).

18909625 is an equidigital number, since it uses as much as digits as its factorization.

18909625 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21633 (or 21623 counting only the distinct ones).

The product of its (nonzero) digits is 38880, while the sum is 40.

The square root of 18909625 is about 4348.5198631258. The cubic root of 18909625 is about 266.4164101826.

The spelling of 18909625 in words is "eighteen million, nine hundred nine thousand, six hundred twenty-five".