20011131 has 40 divisors (see below), whose sum is σ = 35370720. Its totient is φ = 11031552.

The previous prime is 20011099. The next prime is 20011139. The reversal of 20011131 is 13111002.

It is not a de Polignac number, because 20011131 - 2⁵ = 20011099 is a prime.

It is a super-2 number, since 2×20011131² = 800890727798322, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20011139) 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 39 ways as a sum of consecutive naturals, for example, 15835 + ... + 17051.

It is an arithmetic number, because the mean of its divisors is an integer number (884268).

Almost surely, 2^20011131 is an apocalyptic number.

20011131 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

20011131 is a deficient number, since it is larger than the sum of its proper divisors (15359589).

20011131 is a wasteful number, since it uses less digits than its factorization.

20011131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1265 (or 1256 counting only the distinct ones).

The product of its (nonzero) digits is 6, while the sum is 9.

The square root of 20011131 is about 4473.3802655263. The cubic root of 20011131 is about 271.4921092911.

Adding to 20011131 its reverse (13111002), we get a palindrome (33122133).

The spelling of 20011131 in words is "twenty million, eleven thousand, one hundred thirty-one".