51135196961881 has 2 divisors, whose sum is σ = 51135196961882. Its totient is φ = 51135196961880.

The previous prime is 51135196961861. The next prime is 51135196961983. The reversal of 51135196961881 is 18816969153115.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 46870728288400 + 4264468673481 = 6846220^2 + 2065059^2 .

It is a cyclic number.

It is not a de Polignac number, because 51135196961881 - 2²¹ = 51135194864729 is a prime.

It is a super-2 number, since 2×51135196961881² (a number of 28 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (51135196961801) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25567598480940 + 25567598480941.

It is an arithmetic number, because the mean of its divisors is an integer number (25567598480941).

Almost surely, 2^{51135196961881} is an apocalyptic number.

It is an amenable number.

51135196961881 is a deficient number, since it is larger than the sum of its proper divisors (1).

51135196961881 is an equidigital number, since it uses as much as digits as its factorization.

51135196961881 is an evil number, because the sum of its binary digits is even.

The product of its digits is 13996800, while the sum is 64.

The spelling of 51135196961881 in words is "fifty-one trillion, one hundred thirty-five billion, one hundred ninety-six million, nine hundred sixty-one thousand, eight hundred eighty-one".