31220121312169 has 2 divisors, whose sum is σ = 31220121312170. Its totient is φ = 31220121312168.

The previous prime is 31220121312137. The next prime is 31220121312179. The reversal of 31220121312169 is 96121312102213.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 22068498034944 + 9151623277225 = 4697712^2 + 3025165^2 .

It is an emirp because it is prime and its reverse (96121312102213) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 31220121312169 - 2⁵ = 31220121312137 is a prime.

It is a super-2 number, since 2×31220121312169² (a number of 28 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (31220121312119) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15610060656084 + 15610060656085.

It is an arithmetic number, because the mean of its divisors is an integer number (15610060656085).

Almost surely, 2^{31220121312169} is an apocalyptic number.

It is an amenable number.

31220121312169 is a deficient number, since it is larger than the sum of its proper divisors (1).

31220121312169 is an equidigital number, since it uses as much as digits as its factorization.

31220121312169 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7776, while the sum is 34.

The spelling of 31220121312169 in words is "thirty-one trillion, two hundred twenty billion, one hundred twenty-one million, three hundred twelve thousand, one hundred sixty-nine".