131211210310021 has 6 divisors (see below), whose sum is σ = 135891752890322. Its totient is φ = 126686685815760.

The previous prime is 131211210310007. The next prime is 131211210310067. The reversal of 131211210310021 is 120013012112131.

It can be written as a sum of positive squares in 3 ways, for example, as 21651237241921 + 109559973068100 = 4653089^2 + 10467090^2 .

It is not a de Polignac number, because 131211210310021 - 2¹¹ = 131211210307973 is a prime.

It is a super-2 number, since 2×131211210310021² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (131211210310121) 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, 78009042150 + ... + 78009043831.

Almost surely, 2^{131211210310021} is an apocalyptic number.

It is an amenable number.

131211210310021 is a deficient number, since it is larger than the sum of its proper divisors (4680542580301).

131211210310021 is an equidigital number, since it uses as much as digits as its factorization.

131211210310021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 156018086039 (or 156018086010 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 19.

Adding to 131211210310021 its reverse (120013012112131), we get a palindrome (251224222422152).

The spelling of 131211210310021 in words is "one hundred thirty-one trillion, two hundred eleven billion, two hundred ten million, three hundred ten thousand, twenty-one".