166597889 has 4 divisors (see below), whose sum is σ = 168126420. Its totient is φ = 165069360.

The previous prime is 166597877. The next prime is 166597897. The reversal of 166597889 is 988795661.

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 70224400 + 96373489 = 8380^2 + 9817^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-166597889 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (166597819) 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, 764102 + ... + 764319.

It is an arithmetic number, because the mean of its divisors is an integer number (42031605).

Almost surely, 2^166597889 is an apocalyptic number.

It is an amenable number.

166597889 is a deficient number, since it is larger than the sum of its proper divisors (1528531).

166597889 is a wasteful number, since it uses less digits than its factorization.

166597889 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1528530.

The product of its digits is 6531840, while the sum is 59.

The square root of 166597889 is about 12907.2804649159. The cubic root of 166597889 is about 550.2454981166.

The spelling of 166597889 in words is "one hundred sixty-six million, five hundred ninety-seven thousand, eight hundred eighty-nine".