621630 has 24 divisors (see below), whose sum is σ = 1616472. Its totient is φ = 165744.

The previous prime is 621629. The next prime is 621631. The reversal of 621630 is 36126.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (621629) and next prime (621631).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (621631) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3364 + ... + 3543.

It is an arithmetic number, because the mean of its divisors is an integer number (67353).

2⁶²¹⁶³⁰ is an apocalyptic number.

621630 is an abundant number, since it is smaller than the sum of its proper divisors (994842).

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

621630 is a wasteful number, since it uses less digits than its factorization.

621630 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6920 (or 6917 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 18.

The square root of 621630 is about 788.4351590334. The cubic root of 621630 is about 85.3448504692.

Adding to 621630 its reverse (36126), we get a palindrome (657756).

The spelling of 621630 in words is "six hundred twenty-one thousand, six hundred thirty".