221623663 has 2 divisors, whose sum is σ = 221623664. Its totient is φ = 221623662.

The previous prime is 221623651. The next prime is 221623691. The reversal of 221623663 is 366326122.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 221623663 - 2⁹ = 221623151 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (221623063) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110811831 + 110811832.

It is an arithmetic number, because the mean of its divisors is an integer number (110811832).

Almost surely, 2^221623663 is an apocalyptic number.

221623663 is a deficient number, since it is larger than the sum of its proper divisors (1).

221623663 is an equidigital number, since it uses as much as digits as its factorization.

221623663 is an evil number, because the sum of its binary digits is even.

The product of its digits is 15552, while the sum is 31.

The square root of 221623663 is about 14887.0300261671. The cubic root of 221623663 is about 605.1625481319.

Adding to 221623663 its reverse (366326122), we get a palindrome (587949785).

The spelling of 221623663 in words is "two hundred twenty-one million, six hundred twenty-three thousand, six hundred sixty-three".