166320921600 has 396 divisors, whose sum is σ = 602272925280. Its totient is φ = 43848499200.

The previous prime is 166320921593. The next prime is 166320921629. The reversal of 166320921600 is 6129023661.

It is a happy number.

166320921600 is a `hidden beast` number, since 1 + 6 + 6 + 3 + 20 + 9 + 21 + 600 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 20501545 + ... + 20509655.

Almost surely, 2^166320921600 is an apocalyptic number.

166320921600 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 166320921600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (301136462640).

166320921600 is an abundant number, since it is smaller than the sum of its proper divisors (435952003680).

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

166320921600 is a wasteful number, since it uses less digits than its factorization.

166320921600 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8236 (or 8210 counting only the distinct ones).

The product of its (nonzero) digits is 23328, while the sum is 36.

The spelling of 166320921600 in words is "one hundred sixty-six billion, three hundred twenty million, nine hundred twenty-one thousand, six hundred".