31221212201 has 2 divisors, whose sum is σ = 31221212202. Its totient is φ = 31221212200.

The previous prime is 31221212179. The next prime is 31221212203. The reversal of 31221212201 is 10221212213.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21211009600 + 10010202601 = 145640^2 + 100051^2 .

It is a cyclic number.

It is not a de Polignac number, because 31221212201 - 2³⁰ = 30147470377 is a prime.

Together with 31221212203, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 31221212201.

It is not a weakly prime, because it can be changed into another prime (31221212203) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15610606100 + 15610606101.

It is an arithmetic number, because the mean of its divisors is an integer number (15610606101).

Almost surely, 2^31221212201 is an apocalyptic number.

It is an amenable number.

31221212201 is a deficient number, since it is larger than the sum of its proper divisors (1).

31221212201 is an equidigital number, since it uses as much as digits as its factorization.

31221212201 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 96, while the sum is 17.

Adding to 31221212201 its reverse (10221212213), we get a palindrome (41442424414).

The spelling of 31221212201 in words is "thirty-one billion, two hundred twenty-one million, two hundred twelve thousand, two hundred one".