166643942400 has 1584 divisors, whose sum is σ = 698494043520. Its totient is φ = 37630771200.

The previous prime is 166643942369. The next prime is 166643942401. The reversal of 166643942400 is 4249346661.

It is a super-2 number, since 2×166643942400² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (166643942401) by changing a digit.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 2824473571 + ... + 2824473629.

Almost surely, 2^166643942400 is an apocalyptic number.

166643942400 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 166643942400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (349247021760).

166643942400 is an abundant number, since it is smaller than the sum of its proper divisors (531850101120).

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

166643942400 is a wasteful number, since it uses less digits than its factorization.

166643942400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 172 (or 146 counting only the distinct ones).

The product of its (nonzero) digits is 746496, while the sum is 45.

The spelling of 166643942400 in words is "one hundred sixty-six billion, six hundred forty-three million, nine hundred forty-two thousand, four hundred".