621604 has 12 divisors (see below), whose sum is σ = 1145200. Its totient is φ = 294408.

The previous prime is 621583. The next prime is 621611. The reversal of 621604 is 406126.

It is a Harshad number since it is a multiple of its sum of digits (19).

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4014 + ... + 4165.

2⁶²¹⁶⁰⁴ is an apocalyptic number.

It is an amenable number.

621604 is a deficient number, since it is larger than the sum of its proper divisors (523596).

621604 is a wasteful number, since it uses less digits than its factorization.

621604 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8202 (or 8200 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 19.

The square root of 621604 is about 788.4186705044. The cubic root of 621604 is about 85.3436605882.

It can be divided in two parts, 621 and 604, that added together give a triangular number (1225 = T₄₉).

The spelling of 621604 in words is "six hundred twenty-one thousand, six hundred four".