166978749 has 16 divisors (see below), whose sum is σ = 255079040. Its totient is φ = 95178240.

The previous prime is 166978739. The next prime is 166978753. The reversal of 166978749 is 947879661.

It is not a de Polignac number, because 166978749 - 2⁷ = 166978621 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (166978739) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1132 + ... + 18309.

It is an arithmetic number, because the mean of its divisors is an integer number (15942440).

Almost surely, 2^166978749 is an apocalyptic number.

It is an amenable number.

166978749 is a deficient number, since it is larger than the sum of its proper divisors (88100291).

166978749 is a wasteful number, since it uses less digits than its factorization.

166978749 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19860.

The product of its digits is 4572288, while the sum is 57.

The square root of 166978749 is about 12922.0257312853. The cubic root of 166978749 is about 550.6644850303.

The spelling of 166978749 in words is "one hundred sixty-six million, nine hundred seventy-eight thousand, seven hundred forty-nine".