166556394 has 24 divisors (see below), whose sum is σ = 379866240. Its totient is φ = 52596648.

The previous prime is 166556389. The next prime is 166556399. The reversal of 166556394 is 493655661.

166556394 is a `hidden beast` number, since 1 + 6 + 6 + 5 + 5 + 639 + 4 = 666.

It is an interprime number because it is at equal distance from previous prime (166556389) and next prime (166556399).

It is not an unprimeable number, because it can be changed into a prime (166556399) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 243162 + ... + 243845.

It is an arithmetic number, because the mean of its divisors is an integer number (15827760).

Almost surely, 2^166556394 is an apocalyptic number.

166556394 is an abundant number, since it is smaller than the sum of its proper divisors (213309846).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

166556394 is a wasteful number, since it uses less digits than its factorization.

166556394 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 487034 (or 487031 counting only the distinct ones).

The product of its digits is 583200, while the sum is 45.

The square root of 166556394 is about 12905.6729386731. The cubic root of 166556394 is about 550.1998105972.

The spelling of 166556394 in words is "one hundred sixty-six million, five hundred fifty-six thousand, three hundred ninety-four".