5643622661 has 4 divisors (see below), whose sum is σ = 5647149324. Its totient is φ = 5640096000.

The previous prime is 5643622643. The next prime is 5643622729. The reversal of 5643622661 is 1662263465.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 4135776100 + 1507846561 = 64310^2 + 38831^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-5643622661 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (5643622961) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1760930 + ... + 1764131.

It is an arithmetic number, because the mean of its divisors is an integer number (1411787331).

Almost surely, 2^5643622661 is an apocalyptic number.

It is an amenable number.

5643622661 is a deficient number, since it is larger than the sum of its proper divisors (3526663).

5643622661 is a wasteful number, since it uses less digits than its factorization.

5643622661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3526662.

The product of its digits is 311040, while the sum is 41.

The square root of 5643622661 is about 75124.0484864867. The cubic root of 5643622661 is about 1780.4071219792.

It can be divided in two parts, 56436 and 22661, that added together give a palindrome (79097).

The spelling of 5643622661 in words is "five billion, six hundred forty-three million, six hundred twenty-two thousand, six hundred sixty-one".