81744296693 has 2 divisors, whose sum is σ = 81744296694. Its totient is φ = 81744296692.

The previous prime is 81744296681. The next prime is 81744296741. The reversal of 81744296693 is 39669244718.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 80961304369 + 782992324 = 284537^2 + 27982^2 .

It is a cyclic number.

It is not a de Polignac number, because 81744296693 - 2⁴ = 81744296677 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81744226693) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40872148346 + 40872148347.

It is an arithmetic number, because the mean of its divisors is an integer number (40872148347).

Almost surely, 2^81744296693 is an apocalyptic number.

It is an amenable number.

81744296693 is a deficient number, since it is larger than the sum of its proper divisors (1).

81744296693 is an equidigital number, since it uses as much as digits as its factorization.

81744296693 is an evil number, because the sum of its binary digits is even.

The product of its digits is 15676416, while the sum is 59.

The spelling of 81744296693 in words is "eighty-one billion, seven hundred forty-four million, two hundred ninety-six thousand, six hundred ninety-three".