161201977 has 2 divisors, whose sum is σ = 161201978. Its totient is φ = 161201976.

The previous prime is 161201951. The next prime is 161201987. The reversal of 161201977 is 779102161.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 116726416 + 44475561 = 10804^2 + 6669^2 .

It is a cyclic number.

It is not a de Polignac number, because 161201977 - 2⁷ = 161201849 is a prime.

It is not a weakly prime, because it can be changed into another prime (161201987) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80600988 + 80600989.

It is an arithmetic number, because the mean of its divisors is an integer number (80600989).

Almost surely, 2^161201977 is an apocalyptic number.

It is an amenable number.

161201977 is a deficient number, since it is larger than the sum of its proper divisors (1).

161201977 is an equidigital number, since it uses as much as digits as its factorization.

161201977 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5292, while the sum is 34.

The square root of 161201977 is about 12696.5340546151. The cubic root of 161201977 is about 544.2395780544.

The spelling of 161201977 in words is "one hundred sixty-one million, two hundred one thousand, nine hundred seventy-seven".