5211721591 has 2 divisors, whose sum is σ = 5211721592. Its totient is φ = 5211721590.

The previous prime is 5211721589. The next prime is 5211721607. The reversal of 5211721591 is 1951271125.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 5211721591 - 2¹ = 5211721589 is a prime.

Together with 5211721589, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (5211721511) 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, 2605860795 + 2605860796.

It is an arithmetic number, because the mean of its divisors is an integer number (2605860796).

Almost surely, 2^5211721591 is an apocalyptic number.

5211721591 is a deficient number, since it is larger than the sum of its proper divisors (1).

5211721591 is an equidigital number, since it uses as much as digits as its factorization.

5211721591 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6300, while the sum is 34.

The square root of 5211721591 is about 72192.2543698422. The cubic root of 5211721591 is about 1733.7789902603.

The spelling of 5211721591 in words is "five billion, two hundred eleven million, seven hundred twenty-one thousand, five hundred ninety-one".