18808381 has 8 divisors (see below), whose sum is σ = 19502784. Its totient is φ = 18125280.

The previous prime is 18808373. The next prime is 18808417. The reversal of 18808381 is 18380881.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 18808381 - 2³ = 18808373 is a prime.

It is a super-2 number, since 2×18808381² = 707510391682322, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 18808381.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18808301) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 640 + ... + 6166.

It is an arithmetic number, because the mean of its divisors is an integer number (2437848).

Almost surely, 2^18808381 is an apocalyptic number.

It is an amenable number.

18808381 is a deficient number, since it is larger than the sum of its proper divisors (694403).

18808381 is an equidigital number, since it uses as much as digits as its factorization.

18808381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5651.

The product of its (nonzero) digits is 12288, while the sum is 37.

The square root of 18808381 is about 4336.8630368044. The cubic root of 18808381 is about 265.9400858143.

The spelling of 18808381 in words is "eighteen million, eight hundred eight thousand, three hundred eighty-one".