166591489 has 8 divisors (see below), whose sum is σ = 174389760. Its totient is φ = 158944800.

The previous prime is 166591471. The next prime is 166591511. The reversal of 166591489 is 984195661.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 166591489 - 2²⁵ = 133037057 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (166591409) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 35644 + ... + 40045.

It is an arithmetic number, because the mean of its divisors is an integer number (21798720).

Almost surely, 2^166591489 is an apocalyptic number.

It is an amenable number.

166591489 is a deficient number, since it is larger than the sum of its proper divisors (7798271).

166591489 is an equidigital number, since it uses as much as digits as its factorization.

166591489 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 75791.

The product of its digits is 466560, while the sum is 49.

The square root of 166591489 is about 12907.0325404409. The cubic root of 166591489 is about 550.2384519763.

The spelling of 166591489 in words is "one hundred sixty-six million, five hundred ninety-one thousand, four hundred eighty-nine".