51685048861 has 2 divisors, whose sum is σ = 51685048862. Its totient is φ = 51685048860.

The previous prime is 51685048823. The next prime is 51685048867. The reversal of 51685048861 is 16884058615.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 49103900836 + 2581148025 = 221594^2 + 50805^2 .

It is a cyclic number.

It is not a de Polignac number, because 51685048861 - 2¹³ = 51685040669 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 51685048799 and 51685048808.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51685048867) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25842524430 + 25842524431.

It is an arithmetic number, because the mean of its divisors is an integer number (25842524431).

Almost surely, 2^51685048861 is an apocalyptic number.

It is an amenable number.

51685048861 is a deficient number, since it is larger than the sum of its proper divisors (1).

51685048861 is an equidigital number, since it uses as much as digits as its factorization.

51685048861 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1843200, while the sum is 52.

The spelling of 51685048861 in words is "fifty-one billion, six hundred eighty-five million, forty-eight thousand, eight hundred sixty-one".