131223021013 has 6 divisors (see below), whose sum is σ = 152647187766. Its totient is φ = 112476875112.

The previous prime is 131223020963. The next prime is 131223021019. The reversal of 131223021013 is 310120322131.

It can be written as a sum of positive squares in only one way, i.e., 125924200164 + 5298820849 = 354858^2 + 72793^2 .

It is not a de Polignac number, because 131223021013 - 2²¹ = 131220923861 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 (131223021019) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1339010370 + ... + 1339010467.

It is an arithmetic number, because the mean of its divisors is an integer number (25441197961).

Almost surely, 2^131223021013 is an apocalyptic number.

It is an amenable number.

131223021013 is a deficient number, since it is larger than the sum of its proper divisors (21424166753).

131223021013 is an equidigital number, since it uses as much as digits as its factorization.

131223021013 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2678020851 (or 2678020844 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 19.

Adding to 131223021013 its reverse (310120322131), we get a palindrome (441343343144).

The spelling of 131223021013 in words is "one hundred thirty-one billion, two hundred twenty-three million, twenty-one thousand, thirteen".