81765875747 has 2 divisors, whose sum is σ = 81765875748. Its totient is φ = 81765875746.

The previous prime is 81765875731. The next prime is 81765875767. The reversal of 81765875747 is 74757856718.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 81765875747 - 2⁴ = 81765875731 is a prime.

It is not a weakly prime, because it can be changed into another prime (81765875707) 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, 40882937873 + 40882937874.

It is an arithmetic number, because the mean of its divisors is an integer number (40882937874).

Almost surely, 2^81765875747 is an apocalyptic number.

81765875747 is a deficient number, since it is larger than the sum of its proper divisors (1).

81765875747 is an equidigital number, since it uses as much as digits as its factorization.

81765875747 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 92198400, while the sum is 65.

The spelling of 81765875747 in words is "eighty-one billion, seven hundred sixty-five million, eight hundred seventy-five thousand, seven hundred forty-seven".