20404131 has 32 divisors (see below), whose sum is σ = 32306688. Its totient is φ = 11312640.

The previous prime is 20404127. The next prime is 20404133. The reversal of 20404131 is 13140402.

It is not a de Polignac number, because 20404131 - 2² = 20404127 is a prime.

It is a super-2 number, since 2×20404131² = 832657123730322, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 20404131.

It is not an unprimeable number, because it can be changed into a prime (20404133) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 20266 + ... + 21248.

It is an arithmetic number, because the mean of its divisors is an integer number (1009584).

Almost surely, 2^20404131 is an apocalyptic number.

20404131 is a deficient number, since it is larger than the sum of its proper divisors (11902557).

20404131 is a wasteful number, since it uses less digits than its factorization.

20404131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1051.

The product of its (nonzero) digits is 96, while the sum is 15.

The square root of 20404131 is about 4517.0932024921. The cubic root of 20404131 is about 273.2578840269.

Adding to 20404131 its reverse (13140402), we get a palindrome (33544533).

The spelling of 20404131 in words is "twenty million, four hundred four thousand, one hundred thirty-one".