221387863 has 2 divisors, whose sum is σ = 221387864. Its totient is φ = 221387862.

The previous prime is 221387839. The next prime is 221387893. The reversal of 221387863 is 368783122.

221387863 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 221387863 - 2¹³ = 221379671 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221387893) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110693931 + 110693932.

It is an arithmetic number, because the mean of its divisors is an integer number (110693932).

Almost surely, 2^221387863 is an apocalyptic number.

221387863 is a deficient number, since it is larger than the sum of its proper divisors (1).

221387863 is an equidigital number, since it uses as much as digits as its factorization.

221387863 is an evil number, because the sum of its binary digits is even.

The product of its digits is 96768, while the sum is 40.

The square root of 221387863 is about 14879.1082730115. The cubic root of 221387863 is about 604.9478478825.

The spelling of 221387863 in words is "two hundred twenty-one million, three hundred eighty-seven thousand, eight hundred sixty-three".