161803897 has 2 divisors, whose sum is σ = 161803898. Its totient is φ = 161803896.

The previous prime is 161803823. The next prime is 161803913. The reversal of 161803897 is 798308161.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 83375161 + 78428736 = 9131^2 + 8856^2 .

It is a cyclic number.

It is not a de Polignac number, because 161803897 - 2²³ = 153415289 is a prime.

It is not a weakly prime, because it can be changed into another prime (161804897) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80901948 + 80901949.

It is an arithmetic number, because the mean of its divisors is an integer number (80901949).

Almost surely, 2^161803897 is an apocalyptic number.

It is an amenable number.

161803897 is a deficient number, since it is larger than the sum of its proper divisors (1).

161803897 is an equidigital number, since it uses as much as digits as its factorization.

161803897 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 72576, while the sum is 43.

The square root of 161803897 is about 12720.2160752088. The cubic root of 161803897 is about 544.9161243421.

The spelling of 161803897 in words is "one hundred sixty-one million, eight hundred three thousand, eight hundred ninety-seven".