161600506961 has 2 divisors, whose sum is σ = 161600506962. Its totient is φ = 161600506960.

The previous prime is 161600506909. The next prime is 161600506987. The reversal of 161600506961 is 169605006161.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 147241038400 + 14359468561 = 383720^2 + 119831^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-161600506961 is a prime.

It is a super-2 number, since 2×161600506961² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (161600506861) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80800253480 + 80800253481.

It is an arithmetic number, because the mean of its divisors is an integer number (80800253481).

Almost surely, 2^161600506961 is an apocalyptic number.

It is an amenable number.

161600506961 is a deficient number, since it is larger than the sum of its proper divisors (1).

161600506961 is an equidigital number, since it uses as much as digits as its factorization.

161600506961 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 58320, while the sum is 41.

The spelling of 161600506961 in words is "one hundred sixty-one billion, six hundred million, five hundred six thousand, nine hundred sixty-one".