81892397605751 has 32 divisors (see below), whose sum is σ = 87486001827840. Its totient is φ = 76482739517184.

The previous prime is 81892397605741. The next prime is 81892397605783. The reversal of 81892397605751 is 15750679329818.

It is a de Polignac number, because none of the positive numbers 2^k-81892397605751 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81892397605721) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 807033320 + ... + 807134786.

It is an arithmetic number, because the mean of its divisors is an integer number (2733937557120).

Almost surely, 2^{81892397605751} is an apocalyptic number.

81892397605751 is a deficient number, since it is larger than the sum of its proper divisors (5593604222089).

81892397605751 is a wasteful number, since it uses less digits than its factorization.

81892397605751 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 104735.

The product of its (nonzero) digits is 228614400, while the sum is 71.

The spelling of 81892397605751 in words is "eighty-one trillion, eight hundred ninety-two billion, three hundred ninety-seven million, six hundred five thousand, seven hundred fifty-one".