18808481 has 4 divisors (see below), whose sum is σ = 19163412. Its totient is φ = 18453552.

The previous prime is 18808453. The next prime is 18808487. The reversal of 18808481 is 18480881.

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

It can be written as a sum of positive squares in 2 ways, for example, as 11833600 + 6974881 = 3440^2 + 2641^2 .

It is a cyclic number.

It is not a de Polignac number, because 18808481 - 2⁶ = 18808417 is a prime.

It is a super-2 number, since 2×18808481² = 707517915054722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18808487) 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, 177386 + ... + 177491.

It is an arithmetic number, because the mean of its divisors is an integer number (4790853).

Almost surely, 2^18808481 is an apocalyptic number.

It is an amenable number.

18808481 is a deficient number, since it is larger than the sum of its proper divisors (354931).

18808481 is an equidigital number, since it uses as much as digits as its factorization.

18808481 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 354930.

The product of its (nonzero) digits is 16384, while the sum is 38.

The square root of 18808481 is about 4336.8745658596. The cubic root of 18808481 is about 265.9405571283.

The spelling of 18808481 in words is "eighteen million, eight hundred eight thousand, four hundred eighty-one".