31122121117 has 2 divisors, whose sum is σ = 31122121118. Its totient is φ = 31122121116.

The previous prime is 31122121103. The next prime is 31122121189. The reversal of 31122121117 is 71112122113.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20755012356 + 10367108761 = 144066^2 + 101819^2 .

It is a cyclic number.

It is not a de Polignac number, because 31122121117 - 2¹⁹ = 31121596829 is a prime.

It is a super-3 number, since 3×31122121117³ (a number of 32 digits) contains 333 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31122121717) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15561060558 + 15561060559.

It is an arithmetic number, because the mean of its divisors is an integer number (15561060559).

Almost surely, 2^31122121117 is an apocalyptic number.

It is an amenable number.

31122121117 is a deficient number, since it is larger than the sum of its proper divisors (1).

31122121117 is an equidigital number, since it uses as much as digits as its factorization.

31122121117 is an evil number, because the sum of its binary digits is even.

The product of its digits is 168, while the sum is 22.

The spelling of 31122121117 in words is "thirty-one billion, one hundred twenty-two million, one hundred twenty-one thousand, one hundred seventeen".