621916 has 12 divisors (see below), whose sum is σ = 1095640. Its totient is φ = 308880.

The previous prime is 621913. The next prime is 621923. The reversal of 621916 is 619126.

It is a super-2 number, since 2×621916² = 773559022112, which contains 22 as substring.

It is a nialpdrome in base 15.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (621913) 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, 295 + ... + 1153.

2⁶²¹⁹¹⁶ is an apocalyptic number.

It is an amenable number.

621916 is a deficient number, since it is larger than the sum of its proper divisors (473724).

621916 is a wasteful number, since it uses less digits than its factorization.

621916 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1044 (or 1042 counting only the distinct ones).

The product of its digits is 648, while the sum is 25.

The square root of 621916 is about 788.6165100985. The cubic root of 621916 is about 85.3579369702.

The spelling of 621916 in words is "six hundred twenty-one thousand, nine hundred sixteen".