166551840 has 576 divisors, whose sum is σ = 739694592. Its totient is φ = 33177600.

The previous prime is 166551823. The next prime is 166551863. The reversal of 166551840 is 48155661.

166551840 is a `hidden beast` number, since 1 + 66 + 551 + 8 + 40 = 666.

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

It is a junction number, because it is equal to n+sod(n) for n = 166551795 and 166551804.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 4062220 + ... + 4062260.

It is an arithmetic number, because the mean of its divisors is an integer number (1284192).

Almost surely, 2^166551840 is an apocalyptic number.

166551840 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 166551840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (369847296).

166551840 is an abundant number, since it is smaller than the sum of its proper divisors (573142752).

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

166551840 is a wasteful number, since it uses less digits than its factorization.

166551840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 113 (or 102 counting only the distinct ones).

The product of its (nonzero) digits is 28800, while the sum is 36.

The square root of 166551840 is about 12905.4965034283. The cubic root of 166551840 is about 550.1947960138.

The spelling of 166551840 in words is "one hundred sixty-six million, five hundred fifty-one thousand, eight hundred forty".