18640907 has 4 divisors (see below), whose sum is σ = 18783336. Its totient is φ = 18498480.

The previous prime is 18640903. The next prime is 18640913. The reversal of 18640907 is 70904681.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 18640907 - 2² = 18640903 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18640903) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 71018 + ... + 71279.

It is an arithmetic number, because the mean of its divisors is an integer number (4695834).

Almost surely, 2^18640907 is an apocalyptic number.

18640907 is a deficient number, since it is larger than the sum of its proper divisors (142429).

18640907 is a wasteful number, since it uses less digits than its factorization.

18640907 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 142428.

The product of its (nonzero) digits is 12096, while the sum is 35.

The square root of 18640907 is about 4317.5116676160. The cubic root of 18640907 is about 265.1484015115.

The spelling of 18640907 in words is "eighteen million, six hundred forty thousand, nine hundred seven".