172821828 has 12 divisors (see below), whose sum is σ = 403250960. Its totient is φ = 57607272.

The previous prime is 172821827. The next prime is 172821829. The reversal of 172821828 is 828128271.

It is an interprime number because it is at equal distance from previous prime (172821827) and next prime (172821829).

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

It is not an unprimeable number, because it can be changed into a prime (172821821) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7200898 + ... + 7200921.

Almost surely, 2^172821828 is an apocalyptic number.

It is an amenable number.

172821828 is an abundant number, since it is smaller than the sum of its proper divisors (230429132).

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

172821828 is a wasteful number, since it uses less digits than its factorization.

172821828 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14401826 (or 14401824 counting only the distinct ones).

The product of its digits is 28672, while the sum is 39.

The square root of 172821828 is about 13146.1716100164. The cubic root of 172821828 is about 557.0141119630.

It can be divided in two parts, 17282 and 1828, that added together give a triangular number (19110 = T₁₉₅).

The spelling of 172821828 in words is "one hundred seventy-two million, eight hundred twenty-one thousand, eight hundred twenty-eight".