166003399 has 4 divisors (see below), whose sum is σ = 174740440. Its totient is φ = 157266360.

The previous prime is 166003393. The next prime is 166003417. The reversal of 166003399 is 993300661.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 166003399 - 2¹⁷ = 165872327 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (166003393) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4368492 + ... + 4368529.

It is an arithmetic number, because the mean of its divisors is an integer number (43685110).

Almost surely, 2^166003399 is an apocalyptic number.

166003399 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

166003399 is a deficient number, since it is larger than the sum of its proper divisors (8737041).

166003399 is an equidigital number, since it uses as much as digits as its factorization.

166003399 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8737040.

The product of its (nonzero) digits is 26244, while the sum is 37.

The square root of 166003399 is about 12884.2306328317. The cubic root of 166003399 is about 549.5902170771.

The spelling of 166003399 in words is "one hundred sixty-six million, three thousand, three hundred ninety-nine".