166821828 has 12 divisors (see below), whose sum is σ = 389250960. Its totient is φ = 55607272.

The previous prime is 166821827. The next prime is 166821841. The reversal of 166821828 is 828128661.

It is a tau number, because it is divible by the number of its divisors (12).

It is a self number, because there is not a number n which added to its sum of digits gives 166821828.

It is not an unprimeable number, because it can be changed into a prime (166821827) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6950898 + ... + 6950921.

It is an arithmetic number, because the mean of its divisors is an integer number (32437580).

Almost surely, 2^166821828 is an apocalyptic number.

It is an amenable number.

166821828 is an abundant number, since it is smaller than the sum of its proper divisors (222429132).

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

166821828 is a wasteful number, since it uses less digits than its factorization.

166821828 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13901826 (or 13901824 counting only the distinct ones).

The product of its digits is 73728, while the sum is 42.

The square root of 166821828 is about 12915.9524619751. The cubic root of 166821828 is about 550.4919323253.

The spelling of 166821828 in words is "one hundred sixty-six million, eight hundred twenty-one thousand, eight hundred twenty-eight".