51501020689 has 2 divisors, whose sum is σ = 51501020690. Its totient is φ = 51501020688.

The previous prime is 51501020687. The next prime is 51501020707. The reversal of 51501020689 is 98602010515.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 50661006400 + 840014289 = 225080^2 + 28983^2 .

It is a cyclic number.

It is not a de Polignac number, because 51501020689 - 2¹ = 51501020687 is a prime.

Together with 51501020687, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (51501020687) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25750510344 + 25750510345.

It is an arithmetic number, because the mean of its divisors is an integer number (25750510345).

Almost surely, 2^51501020689 is an apocalyptic number.

It is an amenable number.

51501020689 is a deficient number, since it is larger than the sum of its proper divisors (1).

51501020689 is an equidigital number, since it uses as much as digits as its factorization.

51501020689 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 21600, while the sum is 37.

The spelling of 51501020689 in words is "fifty-one billion, five hundred one million, twenty thousand, six hundred eighty-nine".