81073592780 has 24 divisors (see below), whose sum is σ = 171907505952. Its totient is φ = 32114587392.

The previous prime is 81073592777. The next prime is 81073592783. The reversal of 81073592780 is 8729537018.

It is an interprime number because it is at equal distance from previous prime (81073592777) and next prime (81073592783).

It is not an unprimeable number, because it can be changed into a prime (81073592783) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19675997 + ... + 19680116.

It is an arithmetic number, because the mean of its divisors is an integer number (7162812748).

Almost surely, 2^81073592780 is an apocalyptic number.

It is an amenable number.

81073592780 is an abundant number, since it is smaller than the sum of its proper divisors (90833913172).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81073592780 is a wasteful number, since it uses less digits than its factorization.

81073592780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39356225 (or 39356223 counting only the distinct ones).

The product of its (nonzero) digits is 846720, while the sum is 50.

The spelling of 81073592780 in words is "eighty-one billion, seventy-three million, five hundred ninety-two thousand, seven hundred eighty".