18906939 has 10 divisors (see below), whose sum is σ = 28243820. Its totient is φ = 12604572.

The previous prime is 18906917. The next prime is 18906961. The reversal of 18906939 is 93960981.

It is an interprime number because it is at equal distance from previous prime (18906917) and next prime (18906961).

It is not a de Polignac number, because 18906939 - 2⁹ = 18906427 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 18906894 and 18906903.

It is not an unprimeable number, because it can be changed into a prime (18904939) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 116629 + ... + 116790.

It is an arithmetic number, because the mean of its divisors is an integer number (2824382).

Almost surely, 2^18906939 is an apocalyptic number.

18906939 is a deficient number, since it is larger than the sum of its proper divisors (9336881).

18906939 is an equidigital number, since it uses as much as digits as its factorization.

18906939 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 233431 (or 233422 counting only the distinct ones).

The product of its (nonzero) digits is 104976, while the sum is 45.

The square root of 18906939 is about 4348.2110114391. The cubic root of 18906939 is about 266.4037952953.

The spelling of 18906939 in words is "eighteen million, nine hundred six thousand, nine hundred thirty-nine".