81037517278 has 48 divisors (see below), whose sum is σ = 125873318160. Its totient is φ = 39116892672.

The previous prime is 81037517273. The next prime is 81037517279. The reversal of 81037517278 is 87271573018.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81037517273) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 258905650 + ... + 258905962.

It is an arithmetic number, because the mean of its divisors is an integer number (2622360795).

Almost surely, 2^81037517278 is an apocalyptic number.

81037517278 is a deficient number, since it is larger than the sum of its proper divisors (44835800882).

81037517278 is a wasteful number, since it uses less digits than its factorization.

81037517278 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 829 (or 740 counting only the distinct ones).

The product of its (nonzero) digits is 658560, while the sum is 49.

The spelling of 81037517278 in words is "eighty-one billion, thirty-seven million, five hundred seventeen thousand, two hundred seventy-eight".