131211021213 has 6 divisors (see below), whose sum is σ = 189527030654. Its totient is φ = 87474014136.

The previous prime is 131211021209. The next prime is 131211021247. The reversal of 131211021213 is 312120112131.

It can be written as a sum of positive squares in only one way, i.e., 92156566329 + 39054454884 = 303573^2 + 197622^2 .

It is not a de Polignac number, because 131211021213 - 2² = 131211021209 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 (131211021283) 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, 7289501170 + ... + 7289501187.

Almost surely, 2^131211021213 is an apocalyptic number.

It is an amenable number.

131211021213 is a deficient number, since it is larger than the sum of its proper divisors (58316009441).

131211021213 is a wasteful number, since it uses less digits than its factorization.

131211021213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14579002363 (or 14579002360 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 18.

Adding to 131211021213 its reverse (312120112131), we get a palindrome (443331133344).

The spelling of 131211021213 in words is "one hundred thirty-one billion, two hundred eleven million, twenty-one thousand, two hundred thirteen".