81848684893 has 2 divisors, whose sum is σ = 81848684894. Its totient is φ = 81848684892.

The previous prime is 81848684821. The next prime is 81848684923. The reversal of 81848684893 is 39848684818.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 61604232804 + 20244452089 = 248202^2 + 142283^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81848684893 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81848684693) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40924342446 + 40924342447.

It is an arithmetic number, because the mean of its divisors is an integer number (40924342447).

Almost surely, 2^81848684893 is an apocalyptic number.

It is an amenable number.

81848684893 is a deficient number, since it is larger than the sum of its proper divisors (1).

81848684893 is an equidigital number, since it uses as much as digits as its factorization.

81848684893 is an evil number, because the sum of its binary digits is even.

The product of its digits is 84934656, while the sum is 67.

The spelling of 81848684893 in words is "eighty-one billion, eight hundred forty-eight million, six hundred eighty-four thousand, eight hundred ninety-three".