166656820 has 96 divisors (see below), whose sum is σ = 397393920. Its totient is φ = 58181760.

The previous prime is 166656739. The next prime is 166656821. The reversal of 166656820 is 28656661.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (166656821) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 747229 + ... + 747451.

It is an arithmetic number, because the mean of its divisors is an integer number (4139520).

Almost surely, 2^166656820 is an apocalyptic number.

166656820 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 166656820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (198696960).

166656820 is an abundant number, since it is smaller than the sum of its proper divisors (230737100).

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

166656820 is a wasteful number, since it uses less digits than its factorization.

166656820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 365 (or 363 counting only the distinct ones).

The product of its (nonzero) digits is 103680, while the sum is 40.

The square root of 166656820 is about 12909.5631219650. The cubic root of 166656820 is about 550.3103702767.

The spelling of 166656820 in words is "one hundred sixty-six million, six hundred fifty-six thousand, eight hundred twenty".