646589161 has 2 divisors, whose sum is σ = 646589162. Its totient is φ = 646589160.

The previous prime is 646589143. The next prime is 646589231. The reversal of 646589161 is 161985646.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 338376025 + 308213136 = 18395^2 + 17556^2 .

It is a cyclic number.

It is not a de Polignac number, because 646589161 - 2⁵ = 646589129 is a prime.

It is not a weakly prime, because it can be changed into another prime (646589561) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 323294580 + 323294581.

It is an arithmetic number, because the mean of its divisors is an integer number (323294581).

Almost surely, 2^646589161 is an apocalyptic number.

It is an amenable number.

646589161 is a deficient number, since it is larger than the sum of its proper divisors (1).

646589161 is an equidigital number, since it uses as much as digits as its factorization.

646589161 is an evil number, because the sum of its binary digits is even.

The product of its digits is 311040, while the sum is 46.

The square root of 646589161 is about 25428.1175276504. The cubic root of 646589161 is about 864.7212667359.

The spelling of 646589161 in words is "six hundred forty-six million, five hundred eighty-nine thousand, one hundred sixty-one".