51878374993 has 2 divisors, whose sum is σ = 51878374994. Its totient is φ = 51878374992.

The previous prime is 51878374981. The next prime is 51878374997. The reversal of 51878374993 is 39947387815.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 29871245889 + 22007129104 = 172833^2 + 148348^2 .

It is a cyclic number.

It is not a de Polignac number, because 51878374993 - 2²¹ = 51876277841 is a prime.

It is not a weakly prime, because it can be changed into another prime (51878374997) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25939187496 + 25939187497.

It is an arithmetic number, because the mean of its divisors is an integer number (25939187497).

Almost surely, 2^51878374993 is an apocalyptic number.

It is an amenable number.

51878374993 is a deficient number, since it is larger than the sum of its proper divisors (1).

51878374993 is an equidigital number, since it uses as much as digits as its factorization.

51878374993 is an evil number, because the sum of its binary digits is even.

The product of its digits is 45722880, while the sum is 64.

The spelling of 51878374993 in words is "fifty-one billion, eight hundred seventy-eight million, three hundred seventy-four thousand, nine hundred ninety-three".