18128631 has 8 divisors (see below), whose sum is σ = 24824944. Its totient is φ = 11759040.

The previous prime is 18128609. The next prime is 18128687. The reversal of 18128631 is 13682181.

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

It is not a de Polignac number, because 18128631 - 2⁵ = 18128599 is a prime.

It is a super-2 number, since 2×18128631² = 657294523868322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18127631) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 81550 + ... + 81771.

It is an arithmetic number, because the mean of its divisors is an integer number (3103118).

Almost surely, 2^18128631 is an apocalyptic number.

18128631 is a deficient number, since it is larger than the sum of its proper divisors (6696313).

18128631 is a wasteful number, since it uses less digits than its factorization.

18128631 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 163361.

The product of its digits is 2304, while the sum is 30.

The square root of 18128631 is about 4257.7730094499. The cubic root of 18128631 is about 262.6969333983.

The spelling of 18128631 in words is "eighteen million, one hundred twenty-eight thousand, six hundred thirty-one".