51721705571 has 2 divisors, whose sum is σ = 51721705572. Its totient is φ = 51721705570.

The previous prime is 51721705559. The next prime is 51721705591. The reversal of 51721705571 is 17550712715.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 51721705571 - 2¹⁰ = 51721704547 is a prime.

It is not a weakly prime, because it can be changed into another prime (51721705531) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25860852785 + 25860852786.

It is an arithmetic number, because the mean of its divisors is an integer number (25860852786).

Almost surely, 2^51721705571 is an apocalyptic number.

51721705571 is a deficient number, since it is larger than the sum of its proper divisors (1).

51721705571 is an equidigital number, since it uses as much as digits as its factorization.

51721705571 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 85750, while the sum is 41.

The spelling of 51721705571 in words is "fifty-one billion, seven hundred twenty-one million, seven hundred five thousand, five hundred seventy-one".