166256640 has 336 divisors, whose sum is σ = 644048496. Its totient is φ = 39321600.

The previous prime is 166256611. The next prime is 166256663. The reversal of 166256640 is 46652661.

It is a happy number.

166256640 is a `hidden beast` number, since 1 + 6 + 6 + 2 + 5 + 6 + 640 = 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 = 166256595 and 166256604.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 4055020 + ... + 4055060.

It is an arithmetic number, because the mean of its divisors is an integer number (1916811).

Almost surely, 2^166256640 is an apocalyptic number.

166256640 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 166256640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (322024248).

166256640 is an abundant number, since it is smaller than the sum of its proper divisors (477791856).

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

166256640 is a wasteful number, since it uses less digits than its factorization.

166256640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 89 (or 62 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 36.

The square root of 166256640 is about 12894.0544438125. The cubic root of 166256640 is about 549.8695448172.

The spelling of 166256640 in words is "one hundred sixty-six million, two hundred fifty-six thousand, six hundred forty".