166388890 has 16 divisors (see below), whose sum is σ = 315263520. Its totient is φ = 63052560.

The previous prime is 166388861. The next prime is 166388897. The reversal of 166388890 is 98883661.

It is not an unprimeable number, because it can be changed into a prime (166388897) 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, 437676 + ... + 438055.

It is an arithmetic number, because the mean of its divisors is an integer number (19703970).

Almost surely, 2^166388890 is an apocalyptic number.

166388890 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

166388890 is a deficient number, since it is larger than the sum of its proper divisors (148874630).

166388890 is a wasteful number, since it uses less digits than its factorization.

166388890 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 875757.

The product of its (nonzero) digits is 497664, while the sum is 49.

The square root of 166388890 is about 12899.1817569953. The cubic root of 166388890 is about 550.0153053592.

The spelling of 166388890 in words is "one hundred sixty-six million, three hundred eighty-eight thousand, eight hundred ninety".