166389812838 has 48 divisors (see below), whose sum is σ = 369489556800. Its totient is φ = 54083352960.

The previous prime is 166389812819. The next prime is 166389812873. The reversal of 166389812838 is 838218983661.

166389812838 is a `hidden beast` number, since 166 + 389 + 8 + 12 + 83 + 8 = 666.

It is a super-2 number, since 2×166389812838² (a number of 23 digits) contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1441843 + ... + 1552961.

It is an arithmetic number, because the mean of its divisors is an integer number (7697699100).

Almost surely, 2^166389812838 is an apocalyptic number.

166389812838 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

166389812838 is an abundant number, since it is smaller than the sum of its proper divisors (203099743962).

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

166389812838 is a wasteful number, since it uses less digits than its factorization.

166389812838 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 113197 (or 113194 counting only the distinct ones).

The product of its digits is 23887872, while the sum is 63.

The spelling of 166389812838 in words is "one hundred sixty-six billion, three hundred eighty-nine million, eight hundred twelve thousand, eight hundred thirty-eight".