161131777 has 2 divisors, whose sum is σ = 161131778. Its totient is φ = 161131776.

The previous prime is 161131771. The next prime is 161131783. The reversal of 161131777 is 777131161.

It is a balanced prime because it is at equal distance from previous prime (161131771) and next prime (161131783).

It can be written as a sum of positive squares in only one way, i.e., 133263936 + 27867841 = 11544^2 + 5279^2 .

It is a cyclic number.

It is not a de Polignac number, because 161131777 - 2²⁷ = 26914049 is a prime.

It is not a weakly prime, because it can be changed into another prime (161131771) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80565888 + 80565889.

It is an arithmetic number, because the mean of its divisors is an integer number (80565889).

Almost surely, 2^161131777 is an apocalyptic number.

It is an amenable number.

161131777 is a deficient number, since it is larger than the sum of its proper divisors (1).

161131777 is an equidigital number, since it uses as much as digits as its factorization.

161131777 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6174, while the sum is 34.

The square root of 161131777 is about 12693.7692195817. The cubic root of 161131777 is about 544.1605650333.

The spelling of 161131777 in words is "one hundred sixty-one million, one hundred thirty-one thousand, seven hundred seventy-seven".