8563721791 has 2 divisors, whose sum is σ = 8563721792. Its totient is φ = 8563721790.

The previous prime is 8563721753. The next prime is 8563721827. The reversal of 8563721791 is 1971273658.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 8563721791 - 2²¹ = 8561624639 is a prime.

It is a zygodrome in base 2.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (8563721731) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4281860895 + 4281860896.

It is an arithmetic number, because the mean of its divisors is an integer number (4281860896).

Almost surely, 2^8563721791 is an apocalyptic number.

8563721791 is a deficient number, since it is larger than the sum of its proper divisors (1).

8563721791 is an equidigital number, since it uses as much as digits as its factorization.

8563721791 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 635040, while the sum is 49.

The square root of 8563721791 is about 92540.3792460351. The cubic root of 8563721791 is about 2045.9146711263.

The spelling of 8563721791 in words is "eight billion, five hundred sixty-three million, seven hundred twenty-one thousand, seven hundred ninety-one".