621563641 has 8 divisors (see below), whose sum is σ = 646334280. Its totient is φ = 597015552.

The previous prime is 621563617. The next prime is 621563647. The reversal of 621563641 is 146365126.

621563641 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 100400400 + 521163241 = 10020^2 + 22829^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 621563641 - 2⁷ = 621563513 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 621563597 and 621563606.

It is not an unprimeable number, because it can be changed into a prime (621563647) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 49930 + ... + 61123.

It is an arithmetic number, because the mean of its divisors is an integer number (80791785).

Almost surely, 2^621563641 is an apocalyptic number.

It is an amenable number.

621563641 is a deficient number, since it is larger than the sum of its proper divisors (24770639).

621563641 is a wasteful number, since it uses less digits than its factorization.

621563641 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 111275.

The product of its digits is 25920, while the sum is 34.

The square root of 621563641 is about 24931.1780908965. The cubic root of 621563641 is about 853.4181350694.

The spelling of 621563641 in words is "six hundred twenty-one million, five hundred sixty-three thousand, six hundred forty-one".