18908813 has 16 divisors (see below), whose sum is σ = 24215424. Its totient is φ = 14333760.

The previous prime is 18908801. The next prime is 18908821. The reversal of 18908813 is 31880981.

It is not a de Polignac number, because 18908813 - 2⁴ = 18908797 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18908833) 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, 470 + ... + 6167.

It is an arithmetic number, because the mean of its divisors is an integer number (1513464).

Almost surely, 2^18908813 is an apocalyptic number.

It is an amenable number.

18908813 is a deficient number, since it is larger than the sum of its proper divisors (5306611).

18908813 is a wasteful number, since it uses less digits than its factorization.

18908813 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6692.

The product of its (nonzero) digits is 13824, while the sum is 38.

The square root of 18908813 is about 4348.4264970217. The cubic root of 18908813 is about 266.4125967239.

The spelling of 18908813 in words is "eighteen million, nine hundred eight thousand, eight hundred thirteen".