165858914989 has 2 divisors, whose sum is σ = 165858914990. Its totient is φ = 165858914988.

The previous prime is 165858914987. The next prime is 165858915059. The reversal of 165858914989 is 989419858561.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 163952108100 + 1906806889 = 404910^2 + 43667^2 .

It is a cyclic number.

It is not a de Polignac number, because 165858914989 - 2¹ = 165858914987 is a prime.

Together with 165858914987, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (165858914983) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82929457494 + 82929457495.

It is an arithmetic number, because the mean of its divisors is an integer number (82929457495).

Almost surely, 2^165858914989 is an apocalyptic number.

It is an amenable number.

165858914989 is a deficient number, since it is larger than the sum of its proper divisors (1).

165858914989 is an equidigital number, since it uses as much as digits as its factorization.

165858914989 is an evil number, because the sum of its binary digits is even.

The product of its digits is 223948800, while the sum is 73.

The spelling of 165858914989 in words is "one hundred sixty-five billion, eight hundred fifty-eight million, nine hundred fourteen thousand, nine hundred eighty-nine".