159666761 has 4 divisors (see below), whose sum is σ = 160738500. Its totient is φ = 158595024.

The previous prime is 159666757. The next prime is 159666763. The reversal of 159666761 is 167666951.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 6996025 + 152670736 = 2645^2 + 12356^2 .

It is a cyclic number.

It is not a de Polignac number, because 159666761 - 2² = 159666757 is a prime.

It is a super-2 number, since 2×159666761² = 50986949136462242, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (159666763) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 535646 + ... + 535943.

It is an arithmetic number, because the mean of its divisors is an integer number (40184625).

Almost surely, 2^159666761 is an apocalyptic number.

It is an amenable number.

159666761 is a deficient number, since it is larger than the sum of its proper divisors (1071739).

159666761 is a wasteful number, since it uses less digits than its factorization.

159666761 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1071738.

The product of its digits is 408240, while the sum is 47.

The square root of 159666761 is about 12635.9313467587. The cubic root of 159666761 is about 542.5063656017.

The spelling of 159666761 in words is "one hundred fifty-nine million, six hundred sixty-six thousand, seven hundred sixty-one".