166540842259398 has 48 divisors (see below), whose sum is σ = 364233702792960. Its totient is φ = 54991339108848.

The previous prime is 166540842259381. The next prime is 166540842259417. The reversal of 166540842259398 is 893952248045661.

166540842259398 is a `hidden beast` number, since 1 + 6 + 6 + 5 + 4 + 0 + 8 + 4 + 22 + 593 + 9 + 8 = 666.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (31) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 28027911 + ... + 33446157.

It is an arithmetic number, because the mean of its divisors is an integer number (7588202141520).

Almost surely, 2^{166540842259398} is an apocalyptic number.

166540842259398 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

166540842259398 is an abundant number, since it is smaller than the sum of its proper divisors (197692860533562).

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

166540842259398 is a wasteful number, since it uses less digits than its factorization.

166540842259398 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5434321 (or 5434318 counting only the distinct ones).

The product of its (nonzero) digits is 895795200, while the sum is 72.

The spelling of 166540842259398 in words is "one hundred sixty-six trillion, five hundred forty billion, eight hundred forty-two million, two hundred fifty-nine thousand, three hundred ninety-eight".