31213200132221 has 12 divisors (see below), whose sum is σ = 34880255262972. Its totient is φ = 27830964818304.

The previous prime is 31213200132013. The next prime is 31213200132223. The reversal of 31213200132221 is 12223100231213.

It can be written as a sum of positive squares in 2 ways, for example, as 15949527866596 + 15263672265625 = 3993686^2 + 3906875^2 .

It is not a de Polignac number, because 31213200132221 - 2¹⁸ = 31213199870077 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 (31213200132223) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2543027930 + ... + 2543040203.

It is an arithmetic number, because the mean of its divisors is an integer number (2906687938581).

Almost surely, 2^{31213200132221} is an apocalyptic number.

It is an amenable number.

31213200132221 is a deficient number, since it is larger than the sum of its proper divisors (3667055130751).

31213200132221 is a wasteful number, since it uses less digits than its factorization.

31213200132221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5086068188 (or 5086068169 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 23.

Adding to 31213200132221 its reverse (12223100231213), we get a palindrome (43436300363434).

The spelling of 31213200132221 in words is "thirty-one trillion, two hundred thirteen billion, two hundred million, one hundred thirty-two thousand, two hundred twenty-one".