821172 has 24 divisors (see below), whose sum is σ = 2090592. Its totient is φ = 248800.

The previous prime is 821167. The next prime is 821173. The reversal of 821172 is 271128.

821172 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a plaindrome in base 15.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (821173) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2979 + ... + 3242.

It is an arithmetic number, because the mean of its divisors is an integer number (87108).

2⁸²¹¹⁷² is an apocalyptic number.

It is an amenable number.

821172 is an abundant number, since it is smaller than the sum of its proper divisors (1269420).

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

821172 is a wasteful number, since it uses less digits than its factorization.

821172 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6239 (or 6237 counting only the distinct ones).

The product of its digits is 224, while the sum is 21.

The square root of 821172 is about 906.1854114915. The cubic root of 821172 is about 93.6435877053.

The spelling of 821172 in words is "eight hundred twenty-one thousand, one hundred seventy-two".