161106661 has 2 divisors, whose sum is σ = 161106662. Its totient is φ = 161106660.

The previous prime is 161106613. The next prime is 161106683. The reversal of 161106661 is 166601161.

161106661 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 101909025 + 59197636 = 10095^2 + 7694^2 .

It is a cyclic number.

It is not a de Polignac number, because 161106661 - 2¹⁵ = 161073893 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (161106601) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80553330 + 80553331.

It is an arithmetic number, because the mean of its divisors is an integer number (80553331).

Almost surely, 2^161106661 is an apocalyptic number.

It is an amenable number.

161106661 is a deficient number, since it is larger than the sum of its proper divisors (1).

161106661 is an equidigital number, since it uses as much as digits as its factorization.

161106661 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1296, while the sum is 28.

The square root of 161106661 is about 12692.7798767646. The cubic root of 161106661 is about 544.1322903561.

The spelling of 161106661 in words is "one hundred sixty-one million, one hundred six thousand, six hundred sixty-one".