51731758681 has 2 divisors, whose sum is σ = 51731758682. Its totient is φ = 51731758680.

The previous prime is 51731758669. The next prime is 51731758753. The reversal of 51731758681 is 18685713715.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 51661198681 + 70560000 = 227291^2 + 8400^2 .

It is a cyclic number.

It is not a de Polignac number, because 51731758681 - 2²³ = 51723370073 is a prime.

It is a super-4 number, since 4×51731758681⁴ (a number of 44 digits) contains 4444 as substring. Note that it is a super-d number also for d = 2.

It is not a weakly prime, because it can be changed into another prime (51731758381) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25865879340 + 25865879341.

It is an arithmetic number, because the mean of its divisors is an integer number (25865879341).

Almost surely, 2^51731758681 is an apocalyptic number.

It is an amenable number.

51731758681 is a deficient number, since it is larger than the sum of its proper divisors (1).

51731758681 is an equidigital number, since it uses as much as digits as its factorization.

51731758681 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1411200, while the sum is 52.

The spelling of 51731758681 in words is "fifty-one billion, seven hundred thirty-one million, seven hundred fifty-eight thousand, six hundred eighty-one".