165870001291 has 2 divisors, whose sum is σ = 165870001292. Its totient is φ = 165870001290.

The previous prime is 165870001223. The next prime is 165870001303. The reversal of 165870001291 is 192100078561.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 165870001291 - 2²⁵ = 165836446859 is a prime.

It is not a weakly prime, because it can be changed into another prime (165870001201) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82935000645 + 82935000646.

It is an arithmetic number, because the mean of its divisors is an integer number (82935000646).

Almost surely, 2^165870001291 is an apocalyptic number.

165870001291 is a deficient number, since it is larger than the sum of its proper divisors (1).

165870001291 is an equidigital number, since it uses as much as digits as its factorization.

165870001291 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 30240, while the sum is 40.

The spelling of 165870001291 in words is "one hundred sixty-five billion, eight hundred seventy million, one thousand, two hundred ninety-one".