166557911040 has 384 divisors, whose sum is σ = 611191526400. Its totient is φ = 42980474880.

The previous prime is 166557911011. The next prime is 166557911063. The reversal of 166557911040 is 40119755661.

166557911040 is a `hidden beast` number, since 1 + 6 + 6 + 557 + 91 + 1 + 0 + 4 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (384).

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 8561164 + ... + 8580596.

It is an arithmetic number, because the mean of its divisors is an integer number (1591644600).

Almost surely, 2^166557911040 is an apocalyptic number.

166557911040 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 166557911040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (305595763200).

166557911040 is an abundant number, since it is smaller than the sum of its proper divisors (444633615360).

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

166557911040 is a wasteful number, since it uses less digits than its factorization.

166557911040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19500 (or 19474 counting only the distinct ones).

The product of its (nonzero) digits is 226800, while the sum is 45.

The spelling of 166557911040 in words is "one hundred sixty-six billion, five hundred fifty-seven million, nine hundred eleven thousand, forty".