131031021 has 24 divisors (see below), whose sum is σ = 194392800. Its totient is φ = 78437920.

The previous prime is 131031013. The next prime is 131031031. The reversal of 131031021 is 120130131.

It is not a de Polignac number, because 131031021 - 2³ = 131031013 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 131030988 and 131031006.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (131031031) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 27955 + ... + 32303.

It is an arithmetic number, because the mean of its divisors is an integer number (8099700).

Almost surely, 2^131031021 is an apocalyptic number.

131031021 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

131031021 is a deficient number, since it is larger than the sum of its proper divisors (63361779).

131031021 is a wasteful number, since it uses less digits than its factorization.

131031021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4457 (or 4446 counting only the distinct ones).

The product of its (nonzero) digits is 18, while the sum is 12.

The square root of 131031021 is about 11446.8782207203. The cubic root of 131031021 is about 507.9153931988.

Adding to 131031021 its reverse (120130131), we get a palindrome (251161152).

The spelling of 131031021 in words is "one hundred thirty-one million, thirty-one thousand, twenty-one".