6446382278261 has 2 divisors, whose sum is σ = 6446382278262. Its totient is φ = 6446382278260.

The previous prime is 6446382278251. The next prime is 6446382278267. The reversal of 6446382278261 is 1628722836446.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 5107062134161 + 1339320144100 = 2259881^2 + 1157290^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-6446382278261 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 6446382278261.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6446382278267) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3223191139130 + 3223191139131.

It is an arithmetic number, because the mean of its divisors is an integer number (3223191139131).

Almost surely, 2^{6446382278261} is an apocalyptic number.

It is an amenable number.

6446382278261 is a deficient number, since it is larger than the sum of its proper divisors (1).

6446382278261 is an equidigital number, since it uses as much as digits as its factorization.

6446382278261 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 37158912, while the sum is 59.

The spelling of 6446382278261 in words is "six trillion, four hundred forty-six billion, three hundred eighty-two million, two hundred seventy-eight thousand, two hundred sixty-one".