31503221213 has 2 divisors, whose sum is σ = 31503221214. Its totient is φ = 31503221212.

The previous prime is 31503221201. The next prime is 31503221219. The reversal of 31503221213 is 31212230513.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16683080569 + 14820140644 = 129163^2 + 121738^2 .

It is an emirp because it is prime and its reverse (31212230513) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 31503221213 - 2¹² = 31503217117 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31503221219) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15751610606 + 15751610607.

It is an arithmetic number, because the mean of its divisors is an integer number (15751610607).

Almost surely, 2^31503221213 is an apocalyptic number.

It is an amenable number.

31503221213 is a deficient number, since it is larger than the sum of its proper divisors (1).

31503221213 is an equidigital number, since it uses as much as digits as its factorization.

31503221213 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1080, while the sum is 23.

Adding to 31503221213 its reverse (31212230513), we get a palindrome (62715451726).

The spelling of 31503221213 in words is "thirty-one billion, five hundred three million, two hundred twenty-one thousand, two hundred thirteen".