161669797 has 2 divisors, whose sum is σ = 161669798. Its totient is φ = 161669796.

The previous prime is 161669771. The next prime is 161669843. The reversal of 161669797 is 797966161.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 159112996 + 2556801 = 12614^2 + 1599^2 .

It is a cyclic number.

It is not a de Polignac number, because 161669797 - 2¹⁵ = 161637029 is a prime.

It is a super-2 number, since 2×161669797² = 52274246524042418, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (161669197) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80834898 + 80834899.

It is an arithmetic number, because the mean of its divisors is an integer number (80834899).

Almost surely, 2^161669797 is an apocalyptic number.

It is an amenable number.

161669797 is a deficient number, since it is larger than the sum of its proper divisors (1).

161669797 is an equidigital number, since it uses as much as digits as its factorization.

161669797 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 857304, while the sum is 52.

The square root of 161669797 is about 12714.9438457274. The cubic root of 161669797 is about 544.7655440200.

The spelling of 161669797 in words is "one hundred sixty-one million, six hundred sixty-nine thousand, seven hundred ninety-seven".