621621020 has 24 divisors (see below), whose sum is σ = 1306006800. Its totient is φ = 248533632.

The previous prime is 621620999. The next prime is 621621037. The reversal of 621621020 is 20126126.

It is a happy number.

621621020 is digitally balanced in base 6, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 621620983 and 621621001.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 47336 + ... + 59024.

It is an arithmetic number, because the mean of its divisors is an integer number (54416950).

Almost surely, 2^621621020 is an apocalyptic number.

It is an amenable number.

621621020 is an abundant number, since it is smaller than the sum of its proper divisors (684385780).

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

621621020 is a wasteful number, since it uses less digits than its factorization.

621621020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14357 (or 14355 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 20.

The square root of 621621020 is about 24932.3288122069. The cubic root of 621621020 is about 853.4443950634. Note that the first 3 decimals are identical.

Adding to 621621020 its reverse (20126126), we get a palindrome (641747146).

The spelling of 621621020 in words is "six hundred twenty-one million, six hundred twenty-one thousand, twenty".