166400784 has 240 divisors, whose sum is σ = 555589440. Its totient is φ = 47278080.

The previous prime is 166400779. The next prime is 166400813. The reversal of 166400784 is 487004661.

166400784 is a `hidden beast` number, since 1 + 6 + 640 + 0 + 7 + 8 + 4 = 666.

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

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1715424 + ... + 1715520.

It is an arithmetic number, because the mean of its divisors is an integer number (2314956).

Almost surely, 2^166400784 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 166400784, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (277794720).

166400784 is an abundant number, since it is smaller than the sum of its proper divisors (389188656).

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

166400784 is a wasteful number, since it uses less digits than its factorization.

166400784 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 163 (or 132 counting only the distinct ones).

The product of its (nonzero) digits is 32256, while the sum is 36.

The square root of 166400784 is about 12899.6427857519. The cubic root of 166400784 is about 550.0284106536.

The spelling of 166400784 in words is "one hundred sixty-six million, four hundred thousand, seven hundred eighty-four".