621628 has 18 divisors (see below), whose sum is σ = 1251656. Its totient is φ = 264624.

The previous prime is 621619. The next prime is 621629. The reversal of 621628 is 826126.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (621629) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4098 + ... + 4246.

2⁶²¹⁶²⁸ is an apocalyptic number.

It is an amenable number.

621628 is an abundant number, since it is smaller than the sum of its proper divisors (630028).

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

621628 is a wasteful number, since it uses less digits than its factorization.

621628 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 309 (or 158 counting only the distinct ones).

The product of its digits is 1152, while the sum is 25.

The square root of 621628 is about 788.4338906972. The cubic root of 621628 is about 85.3447589410.

The spelling of 621628 in words is "six hundred twenty-one thousand, six hundred twenty-eight".