166390449 has 4 divisors (see below), whose sum is σ = 221853936. Its totient is φ = 110926964.

The previous prime is 166390439. The next prime is 166390453. The reversal of 166390449 is 944093661.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 166390449 - 2⁷ = 166390321 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 166390449.

It is not an unprimeable number, because it can be changed into a prime (166390409) 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, 27731739 + ... + 27731744.

It is an arithmetic number, because the mean of its divisors is an integer number (55463484).

Almost surely, 2^166390449 is an apocalyptic number.

It is an amenable number.

166390449 is a deficient number, since it is larger than the sum of its proper divisors (55463487).

166390449 is an equidigital number, since it uses as much as digits as its factorization.

166390449 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55463486.

The product of its (nonzero) digits is 139968, while the sum is 42.

The square root of 166390449 is about 12899.2421870434. The cubic root of 166390449 is about 550.0170231646.

The spelling of 166390449 in words is "one hundred sixty-six million, three hundred ninety thousand, four hundred forty-nine".