18129631 has 16 divisors (see below), whose sum is σ = 20070400. Its totient is φ = 16275168.

The previous prime is 18129613. The next prime is 18129653. The reversal of 18129631 is 13692181.

It is not a de Polignac number, because 18129631 - 2⁹ = 18129119 is a prime.

It is a super-2 number, since 2×18129631² = 657367040392322, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 18129593 and 18129602.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18129131) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 130360 + ... + 130498.

It is an arithmetic number, because the mean of its divisors is an integer number (1254400).

Almost surely, 2^18129631 is an apocalyptic number.

18129631 is a deficient number, since it is larger than the sum of its proper divisors (1940769).

18129631 is a wasteful number, since it uses less digits than its factorization.

18129631 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 358.

The product of its digits is 2592, while the sum is 31.

The square root of 18129631 is about 4257.8904401123. The cubic root of 18129631 is about 262.7017635498.

The spelling of 18129631 in words is "eighteen million, one hundred twenty-nine thousand, six hundred thirty-one".