20101131 has 6 divisors (see below), whose sum is σ = 29034980. Its totient is φ = 13400748.

The previous prime is 20101129. The next prime is 20101141. The reversal of 20101131 is 13110102.

It is not a de Polignac number, because 20101131 - 2¹ = 20101129 is a prime.

It is a super-2 number, since 2×20101131² = 808110934958322, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (9), and also a Moran number because the ratio is a prime number: 2233459 = 20101131 / (2 + 0 + 1 + 0 + 1 + 1 + 3 + 1).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20101141) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1116721 + ... + 1116738.

Almost surely, 2^20101131 is an apocalyptic number.

20101131 is a deficient number, since it is larger than the sum of its proper divisors (8933849).

20101131 is a wasteful number, since it uses less digits than its factorization.

20101131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2233465 (or 2233462 counting only the distinct ones).

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

The square root of 20101131 is about 4483.4284872182. The cubic root of 20101131 is about 271.8985122749.

Adding to 20101131 its reverse (13110102), we get a palindrome (33211233).

The spelling of 20101131 in words is "twenty million, one hundred one thousand, one hundred thirty-one".