646332556417 has 2 divisors, whose sum is σ = 646332556418. Its totient is φ = 646332556416.

The previous prime is 646332556409. The next prime is 646332556469. The reversal of 646332556417 is 714655233646.

It is a happy number.

It is an a-pointer prime, because the next prime (646332556469) can be obtained adding 646332556417 to its sum of digits (52).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 353520619776 + 292811936641 = 594576^2 + 541121^2 .

It is a cyclic number.

It is not a de Polignac number, because 646332556417 - 2³ = 646332556409 is a prime.

It is not a weakly prime, because it can be changed into another prime (646332556717) 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, 323166278208 + 323166278209.

It is an arithmetic number, because the mean of its divisors is an integer number (323166278209).

Almost surely, 2^646332556417 is an apocalyptic number.

It is an amenable number.

646332556417 is a deficient number, since it is larger than the sum of its proper divisors (1).

646332556417 is an equidigital number, since it uses as much as digits as its factorization.

646332556417 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 10886400, while the sum is 52.

The spelling of 646332556417 in words is "six hundred forty-six billion, three hundred thirty-two million, five hundred fifty-six thousand, four hundred seventeen".