31220100361 has 2 divisors, whose sum is σ = 31220100362. Its totient is φ = 31220100360.

The previous prime is 31220100343. The next prime is 31220100397. The reversal of 31220100361 is 16300102213.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17940995136 + 13279105225 = 133944^2 + 115235^2 .

It is a cyclic number.

It is not a de Polignac number, because 31220100361 - 2¹⁷ = 31219969289 is a prime.

It is not a weakly prime, because it can be changed into another prime (31220100661) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15610050180 + 15610050181.

It is an arithmetic number, because the mean of its divisors is an integer number (15610050181).

Almost surely, 2^31220100361 is an apocalyptic number.

It is an amenable number.

31220100361 is a deficient number, since it is larger than the sum of its proper divisors (1).

31220100361 is an equidigital number, since it uses as much as digits as its factorization.

31220100361 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 216, while the sum is 19.

Adding to 31220100361 its reverse (16300102213), we get a palindrome (47520202574).

The spelling of 31220100361 in words is "thirty-one billion, two hundred twenty million, one hundred thousand, three hundred sixty-one".