166565543040 has 1152 divisors, whose sum is σ = 677058782400. Its totient is φ = 37480955904.

The previous prime is 166565543029. The next prime is 166565543047. The reversal of 166565543040 is 40345565661.

166565543040 is a `hidden beast` number, since 1 + 6 + 6 + 5 + 65 + 543 + 0 + 40 = 666.

It is a tau number, because it is divible by the number of its divisors (1152).

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 (166565543047) 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, 930533671 + ... + 930533849.

Almost surely, 2^166565543040 is an apocalyptic number.

166565543040 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 166565543040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (338529391200).

166565543040 is an abundant number, since it is smaller than the sum of its proper divisors (510493239360).

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

166565543040 is a wasteful number, since it uses less digits than its factorization.

166565543040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 294 (or 262 counting only the distinct ones).

The product of its (nonzero) digits is 1296000, while the sum is 45.

The spelling of 166565543040 in words is "one hundred sixty-six billion, five hundred sixty-five million, five hundred forty-three thousand, forty".