646564733 has 2 divisors, whose sum is σ = 646564734. Its totient is φ = 646564732.

The previous prime is 646564697. The next prime is 646564739. The reversal of 646564733 is 337465646.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 605258404 + 41306329 = 24602^2 + 6427^2 .

It is a cyclic number.

It is not a de Polignac number, because 646564733 - 2¹⁶ = 646499197 is a prime.

It is a super-2 number, since 2×646564733² = 836091907918722578, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (646564739) 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, 323282366 + 323282367.

It is an arithmetic number, because the mean of its divisors is an integer number (323282367).

Almost surely, 2^646564733 is an apocalyptic number.

It is an amenable number.

646564733 is a deficient number, since it is larger than the sum of its proper divisors (1).

646564733 is an equidigital number, since it uses as much as digits as its factorization.

646564733 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1088640, while the sum is 44.

The square root of 646564733 is about 25427.6371886969. The cubic root of 646564733 is about 864.7103769373.

The spelling of 646564733 in words is "six hundred forty-six million, five hundred sixty-four thousand, seven hundred thirty-three".