166397985600 has 1344 divisors, whose sum is σ = 732779384832. Its totient is φ = 31997952000.

The previous prime is 166397985587. The next prime is 166397985629. The reversal of 166397985600 is 6589793661.

It is a tau number, because it is divible by the number of its divisors (1344).

It is a super-2 number, since 2×166397985600² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (60).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 446107014 + ... + 446107386.

Almost surely, 2^166397985600 is an apocalyptic number.

166397985600 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 166397985600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (366389692416).

166397985600 is an abundant number, since it is smaller than the sum of its proper divisors (566381399232).

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

166397985600 is a wasteful number, since it uses less digits than its factorization.

166397985600 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 504 (or 489 counting only the distinct ones).

The product of its (nonzero) digits is 14696640, while the sum is 60.

The spelling of 166397985600 in words is "one hundred sixty-six billion, three hundred ninety-seven million, nine hundred eighty-five thousand, six hundred".