665660159 has 2 divisors, whose sum is σ = 665660160. Its totient is φ = 665660158.

The previous prime is 665660153. The next prime is 665660183. The reversal of 665660159 is 951066566.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 665660159 - 2¹⁶ = 665594623 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 (665660153) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332830079 + 332830080.

It is an arithmetic number, because the mean of its divisors is an integer number (332830080).

Almost surely, 2^665660159 is an apocalyptic number.

665660159 is a deficient number, since it is larger than the sum of its proper divisors (1).

665660159 is an equidigital number, since it uses as much as digits as its factorization.

665660159 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 291600, while the sum is 44.

The square root of 665660159 is about 25800.3906753367. The cubic root of 665660159 is about 873.1406105861.

The spelling of 665660159 in words is "six hundred sixty-five million, six hundred sixty thousand, one hundred fifty-nine".