159718661 has 2 divisors, whose sum is σ = 159718662. Its totient is φ = 159718660.

The previous prime is 159718651. The next prime is 159718667. The reversal of 159718661 is 166817951.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 83156161 + 76562500 = 9119^2 + 8750^2 .

It is a cyclic number.

It is not a de Polignac number, because 159718661 - 2⁶ = 159718597 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (159718667) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 79859330 + 79859331.

It is an arithmetic number, because the mean of its divisors is an integer number (79859331).

Almost surely, 2^159718661 is an apocalyptic number.

It is an amenable number.

159718661 is a deficient number, since it is larger than the sum of its proper divisors (1).

159718661 is an equidigital number, since it uses as much as digits as its factorization.

159718661 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 90720, while the sum is 44.

The square root of 159718661 is about 12637.9848472769. The cubic root of 159718661 is about 542.5651401602.

The spelling of 159718661 in words is "one hundred fifty-nine million, seven hundred eighteen thousand, six hundred sixty-one".