722021 has 4 divisors (see below), whose sum is σ = 745344. Its totient is φ = 698700.

The previous prime is 722011. The next prime is 722023. The reversal of 722021 is 120227.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 120227 = 109 ⋅1103.

It is a cyclic number.

It is not a de Polignac number, because 722021 - 2¹⁰ = 720997 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 721987 and 722005.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 722021.

It is not an unprimeable number, because it can be changed into a prime (722023) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11615 + ... + 11676.

It is an arithmetic number, because the mean of its divisors is an integer number (186336).

2⁷²²⁰²¹ is an apocalyptic number.

It is an amenable number.

722021 is a deficient number, since it is larger than the sum of its proper divisors (23323).

722021 is a wasteful number, since it uses less digits than its factorization.

722021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23322.

The product of its (nonzero) digits is 56, while the sum is 14.

The square root of 722021 is about 849.7181885778. The cubic root of 722021 is about 89.7118769505.

Adding to 722021 its reverse (120227), we get a palindrome (842248).

The spelling of 722021 in words is "seven hundred twenty-two thousand, twenty-one", and thus it is an iban number.