827721 has 6 divisors (see below), whose sum is σ = 1195610. Its totient is φ = 551808.

The previous prime is 827719. The next prime is 827737. The reversal of 827721 is 127728.

It can be written as a sum of positive squares in only one way, i.e., 746496 + 81225 = 864^2 + 285^2 .

It is not a de Polignac number, because 827721 - 2¹ = 827719 is a prime.

It is a d-powerful number, because it can be written as 8⁴ + 2⁴ + 7² + 7⁷ + 2⁴ + 1 .

It is a Duffinian number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 827721.

It is not an unprimeable number, because it can be changed into a prime (827741) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 45976 + ... + 45993.

2⁸²⁷⁷²¹ is an apocalyptic number.

It is an amenable number.

827721 is a deficient number, since it is larger than the sum of its proper divisors (367889).

827721 is a wasteful number, since it uses less digits than its factorization.

827721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 91975 (or 91972 counting only the distinct ones).

The product of its digits is 1568, while the sum is 27.

The square root of 827721 is about 909.7917344096. The cubic root of 827721 is about 93.8918705344.

The spelling of 827721 in words is "eight hundred twenty-seven thousand, seven hundred twenty-one".