621568 has 22 divisors (see below), whose sum is σ = 1244576. Its totient is φ = 310272.

The previous prime is 621541. The next prime is 621583. The reversal of 621568 is 865126.

It is a plaindrome in base 13.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 721 + ... + 1327.

2⁶²¹⁵⁶⁸ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 621568, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (622288).

621568 is an abundant number, since it is smaller than the sum of its proper divisors (623008).

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

621568 is an equidigital number, since it uses as much as digits as its factorization.

621568 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 627 (or 609 counting only the distinct ones).

The product of its digits is 2880, while the sum is 28.

The square root of 621568 is about 788.3958396643. The cubic root of 621568 is about 85.3420130060.

The spelling of 621568 in words is "six hundred twenty-one thousand, five hundred sixty-eight".