646623023 has 2 divisors, whose sum is σ = 646623024. Its totient is φ = 646623022.

The previous prime is 646623011. The next prime is 646623059. The reversal of 646623023 is 320326646.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 646623023 - 2⁶ = 646622959 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (646623083) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 323311511 + 323311512.

It is an arithmetic number, because the mean of its divisors is an integer number (323311512).

Almost surely, 2^646623023 is an apocalyptic number.

646623023 is a deficient number, since it is larger than the sum of its proper divisors (1).

646623023 is an equidigital number, since it uses as much as digits as its factorization.

646623023 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 31104, while the sum is 32.

The square root of 646623023 is about 25428.7833566610. The cubic root of 646623023 is about 864.7363616793.

Adding to 646623023 its reverse (320326646), we get a palindrome (966949669).

The spelling of 646623023 in words is "six hundred forty-six million, six hundred twenty-three thousand, twenty-three".