646222669 has 2 divisors, whose sum is σ = 646222670. Its totient is φ = 646222668.

The previous prime is 646222637. The next prime is 646222673. The reversal of 646222669 is 966222646.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 445632100 + 200590569 = 21110^2 + 14163^2 .

It is a cyclic number.

It is not a de Polignac number, because 646222669 - 2⁵ = 646222637 is a prime.

It is a super-2 number, since 2×646222669² = 835207475858967122, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (646222679) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 323111334 + 323111335.

It is an arithmetic number, because the mean of its divisors is an integer number (323111335).

Almost surely, 2^646222669 is an apocalyptic number.

It is an amenable number.

646222669 is a deficient number, since it is larger than the sum of its proper divisors (1).

646222669 is an equidigital number, since it uses as much as digits as its factorization.

646222669 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 373248, while the sum is 43.

The square root of 646222669 is about 25420.9100741889. The cubic root of 646222669 is about 864.5578588406.

The spelling of 646222669 in words is "six hundred forty-six million, two hundred twenty-two thousand, six hundred sixty-nine".