166922601978 has 64 divisors (see below), whose sum is σ = 375236590464. Its totient is φ = 49071744000.

The previous prime is 166922601971. The next prime is 166922602001. The reversal of 166922601978 is 879106229661.

It is a super-2 number, since 2×166922601978² (a number of 23 digits) contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (166922601971) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 9918 + ... + 577878.

It is an arithmetic number, because the mean of its divisors is an integer number (5863071726).

Almost surely, 2^166922601978 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 166922601978, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (187618295232).

166922601978 is an abundant number, since it is smaller than the sum of its proper divisors (208313988486).

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

166922601978 is a wasteful number, since it uses less digits than its factorization.

166922601978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 568111.

The product of its (nonzero) digits is 3919104, while the sum is 57.

The spelling of 166922601978 in words is "one hundred sixty-six billion, nine hundred twenty-two million, six hundred one thousand, nine hundred seventy-eight".