161501761 has 2 divisors, whose sum is σ = 161501762. Its totient is φ = 161501760.

The previous prime is 161501749. The next prime is 161501773. The reversal of 161501761 is 167105161.

It is a balanced prime because it is at equal distance from previous prime (161501749) and next prime (161501773).

It can be written as a sum of positive squares in only one way, i.e., 147476736 + 14025025 = 12144^2 + 3745^2 .

It is a cyclic number.

It is not a de Polignac number, because 161501761 - 2¹⁷ = 161370689 is a prime.

It is a super-2 number, since 2×161501761² = 52165637612202242, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (161501701) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80750880 + 80750881.

It is an arithmetic number, because the mean of its divisors is an integer number (80750881).

Almost surely, 2^161501761 is an apocalyptic number.

It is an amenable number.

161501761 is a deficient number, since it is larger than the sum of its proper divisors (1).

161501761 is an equidigital number, since it uses as much as digits as its factorization.

161501761 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1260, while the sum is 28.

The square root of 161501761 is about 12708.3343125683. The cubic root of 161501761 is about 544.5767395186.

The spelling of 161501761 in words is "one hundred sixty-one million, five hundred one thousand, seven hundred sixty-one".