31516265161 has 2 divisors, whose sum is σ = 31516265162. Its totient is φ = 31516265160.

The previous prime is 31516265141. The next prime is 31516265173. The reversal of 31516265161 is 16156261513.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21806133561 + 9710131600 = 147669^2 + 98540^2 .

It is a cyclic number.

It is not a de Polignac number, because 31516265161 - 2¹³ = 31516256969 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 31516265161.

It is not a weakly prime, because it can be changed into another prime (31516265111) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15758132580 + 15758132581.

It is an arithmetic number, because the mean of its divisors is an integer number (15758132581).

Almost surely, 2^31516265161 is an apocalyptic number.

It is an amenable number.

31516265161 is a deficient number, since it is larger than the sum of its proper divisors (1).

31516265161 is an equidigital number, since it uses as much as digits as its factorization.

31516265161 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 32400, while the sum is 37.

The spelling of 31516265161 in words is "thirty-one billion, five hundred sixteen million, two hundred sixty-five thousand, one hundred sixty-one".