663221423 has 2 divisors, whose sum is σ = 663221424. Its totient is φ = 663221422.

The previous prime is 663221381. The next prime is 663221441. The reversal of 663221423 is 324122366.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 663221423 - 2⁶ = 663221359 is a prime.

It is a super-2 number, since 2×663221423² = 879725311852289858, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (663221473) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 331610711 + 331610712.

It is an arithmetic number, because the mean of its divisors is an integer number (331610712).

Almost surely, 2^663221423 is an apocalyptic number.

663221423 is a deficient number, since it is larger than the sum of its proper divisors (1).

663221423 is an equidigital number, since it uses as much as digits as its factorization.

663221423 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 10368, while the sum is 29.

The square root of 663221423 is about 25753.0856986110. The cubic root of 663221423 is about 872.0730162009.

Adding to 663221423 its reverse (324122366), we get a palindrome (987343789).

The spelling of 663221423 in words is "six hundred sixty-three million, two hundred twenty-one thousand, four hundred twenty-three".