47781692681 has 2 divisors, whose sum is σ = 47781692682. Its totient is φ = 47781692680.

The previous prime is 47781692633. The next prime is 47781692711. The reversal of 47781692681 is 18629618774.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 39822198025 + 7959494656 = 199555^2 + 89216^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-47781692681 is a prime.

It is a super-2 number, since 2×47781692681² (a number of 22 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 47781692681.

It is not a weakly prime, because it can be changed into another prime (47781692281) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 23890846340 + 23890846341.

It is an arithmetic number, because the mean of its divisors is an integer number (23890846341).

Almost surely, 2^47781692681 is an apocalyptic number.

It is an amenable number.

47781692681 is a deficient number, since it is larger than the sum of its proper divisors (1).

47781692681 is an equidigital number, since it uses as much as digits as its factorization.

47781692681 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 8128512, while the sum is 59.

The spelling of 47781692681 in words is "forty-seven billion, seven hundred eighty-one million, six hundred ninety-two thousand, six hundred eighty-one".