31321112012161 has 2 divisors, whose sum is σ = 31321112012162. Its totient is φ = 31321112012160.

The previous prime is 31321112012149. The next prime is 31321112012213. The reversal of 31321112012161 is 16121021112313.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 24602155523136 + 6718956489025 = 4960056^2 + 2592095^2 .

It is a cyclic number.

It is not a de Polignac number, because 31321112012161 - 2⁵ = 31321112012129 is a prime.

It is not a weakly prime, because it can be changed into another prime (31321112042161) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15660556006080 + 15660556006081.

It is an arithmetic number, because the mean of its divisors is an integer number (15660556006081).

Almost surely, 2^{31321112012161} is an apocalyptic number.

It is an amenable number.

31321112012161 is a deficient number, since it is larger than the sum of its proper divisors (1).

31321112012161 is an equidigital number, since it uses as much as digits as its factorization.

31321112012161 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 432, while the sum is 25.

Adding to 31321112012161 its reverse (16121021112313), we get a palindrome (47442133124474).

The spelling of 31321112012161 in words is "thirty-one trillion, three hundred twenty-one billion, one hundred twelve million, twelve thousand, one hundred sixty-one".