51138778853 has 2 divisors, whose sum is σ = 51138778854. Its totient is φ = 51138778852.

The previous prime is 51138778819. The next prime is 51138778879. The reversal of 51138778853 is 35887783115.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 50982478849 + 156300004 = 225793^2 + 12502^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51138778853 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51138778753) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25569389426 + 25569389427.

It is an arithmetic number, because the mean of its divisors is an integer number (25569389427).

Almost surely, 2^51138778853 is an apocalyptic number.

It is an amenable number.

51138778853 is a deficient number, since it is larger than the sum of its proper divisors (1).

51138778853 is an equidigital number, since it uses as much as digits as its factorization.

51138778853 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5644800, while the sum is 56.

The spelling of 51138778853 in words is "fifty-one billion, one hundred thirty-eight million, seven hundred seventy-eight thousand, eight hundred fifty-three".