221859887 has 4 divisors (see below), whose sum is σ = 224668320. Its totient is φ = 219051456.

The previous prime is 221859857. The next prime is 221859907. The reversal of 221859887 is 788958122.

It is a happy number.

221859887 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221859887 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221859857) 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, 1404098 + ... + 1404255.

It is an arithmetic number, because the mean of its divisors is an integer number (56167080).

Almost surely, 2^221859887 is an apocalyptic number.

221859887 is a deficient number, since it is larger than the sum of its proper divisors (2808433).

221859887 is an equidigital number, since it uses as much as digits as its factorization.

221859887 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2808432.

The product of its digits is 645120, while the sum is 50.

The square root of 221859887 is about 14894.9617992125. The cubic root of 221859887 is about 605.3774817952.

The spelling of 221859887 in words is "two hundred twenty-one million, eight hundred fifty-nine thousand, eight hundred eighty-seven".