722821 has 8 divisors (see below), whose sum is σ = 823104. Its totient is φ = 628320.

The previous prime is 722819. The next prime is 722833. The reversal of 722821 is 128227.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 722821 - 2¹ = 722819 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 722792 and 722801.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (722881) 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, 1176 + ... + 1681.

It is an arithmetic number, because the mean of its divisors is an integer number (102888).

2⁷²²⁸²¹ is an apocalyptic number.

It is an amenable number.

722821 is a deficient number, since it is larger than the sum of its proper divisors (100283).

722821 is a wasteful number, since it uses less digits than its factorization.

722821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2891.

The product of its digits is 448, while the sum is 22.

The square root of 722821 is about 850.1888025609. The cubic root of 722821 is about 89.7449983376.

The spelling of 722821 in words is "seven hundred twenty-two thousand, eight hundred twenty-one".