668820023 has 2 divisors, whose sum is σ = 668820024. Its totient is φ = 668820022.

The previous prime is 668819999. The next prime is 668820037. The reversal of 668820023 is 320028866.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-668820023 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (668820623) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 334410011 + 334410012.

It is an arithmetic number, because the mean of its divisors is an integer number (334410012).

Almost surely, 2^668820023 is an apocalyptic number.

668820023 is a deficient number, since it is larger than the sum of its proper divisors (1).

668820023 is an equidigital number, since it uses as much as digits as its factorization.

668820023 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 27648, while the sum is 35.

The square root of 668820023 is about 25861.5549223166. The cubic root of 668820023 is about 874.5200188770.

Adding to 668820023 its reverse (320028866), we get a palindrome (988848889).

The spelling of 668820023 in words is "six hundred sixty-eight million, eight hundred twenty thousand, twenty-three".