81771413337044 has 12 divisors (see below), whose sum is σ = 143100335357364. Its totient is φ = 40885603234944.

The previous prime is 81771413337037. The next prime is 81771413337121. The reversal of 81771413337044 is 44073331417718.

It can be written as a sum of positive squares in 2 ways, for example, as 53673059916100 + 28098353420944 = 7326190^2 + 5300788^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 24065807 + ... + 27252630.

It is an arithmetic number, because the mean of its divisors is an integer number (11925027946447).

Almost surely, 2^{81771413337044} is an apocalyptic number.

It is an amenable number.

81771413337044 is a deficient number, since it is larger than the sum of its proper divisors (61328922020320).

81771413337044 is a wasteful number, since it uses less digits than its factorization.

81771413337044 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51716794 (or 51716792 counting only the distinct ones).

The product of its (nonzero) digits is 4741632, while the sum is 53.

The spelling of 81771413337044 in words is "eighty-one trillion, seven hundred seventy-one billion, four hundred thirteen million, three hundred thirty-seven thousand, forty-four".