131331020021 has 4 divisors (see below), whose sum is σ = 131332492044. Its totient is φ = 131329548000.

The previous prime is 131331020011. The next prime is 131331020033. The reversal of 131331020021 is 120020133131.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 120020133131 = 449 ⋅267305419.

It can be written as a sum of positive squares in 2 ways, for example, as 4300080625 + 127030939396 = 65575^2 + 356414^2 .

It is a cyclic number.

It is not a de Polignac number, because 131331020021 - 2¹⁰ = 131331018997 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (131331020011) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 592910 + ... + 783711.

It is an arithmetic number, because the mean of its divisors is an integer number (32833123011).

Almost surely, 2^131331020021 is an apocalyptic number.

It is an amenable number.

131331020021 is a deficient number, since it is larger than the sum of its proper divisors (1472023).

131331020021 is an equidigital number, since it uses as much as digits as its factorization.

131331020021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1472022.

The product of its (nonzero) digits is 108, while the sum is 17.

Adding to 131331020021 its reverse (120020133131), we get a palindrome (251351153152).

It can be divided in two parts, 1313310 and 20021, that added together give a palindrome (1333331).

The spelling of 131331020021 in words is "one hundred thirty-one billion, three hundred thirty-one million, twenty thousand, twenty-one".