622821 has 16 divisors (see below), whose sum is σ = 885248. Its totient is φ = 388800.

The previous prime is 622813. The next prime is 622849. The reversal of 622821 is 128226.

It is not a de Polignac number, because 622821 - 2³ = 622813 is a prime.

It is a Duffinian number.

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 622821.

It is not an unprimeable number, because it can be changed into a prime (622861) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3351 + ... + 3531.

It is an arithmetic number, because the mean of its divisors is an integer number (55328).

2⁶²²⁸²¹ is an apocalyptic number.

It is an amenable number.

622821 is a deficient number, since it is larger than the sum of its proper divisors (262427).

622821 is a wasteful number, since it uses less digits than its factorization.

622821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 252.

The product of its digits is 384, while the sum is 21.

The square root of 622821 is about 789.1900911694. The cubic root of 622821 is about 85.3993206366.

The spelling of 622821 in words is "six hundred twenty-two thousand, eight hundred twenty-one".