81271034491780 has 48 divisors (see below), whose sum is σ = 195925148697600. Its totient is φ = 27739402409088.

The previous prime is 81271034491771. The next prime is 81271034491781. The reversal of 81271034491780 is 8719443017218.

It is not an unprimeable number, because it can be changed into a prime (81271034491781) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1301554855 + ... + 1301617294.

It is an arithmetic number, because the mean of its divisors is an integer number (4081773931200).

Almost surely, 2^{81271034491780} is an apocalyptic number.

It is an amenable number.

81271034491780 is an abundant number, since it is smaller than the sum of its proper divisors (114654114205820).

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

81271034491780 is a wasteful number, since it uses less digits than its factorization.

81271034491780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2603172388 (or 2603172386 counting only the distinct ones).

The product of its (nonzero) digits is 2709504, while the sum is 55.

The spelling of 81271034491780 in words is "eighty-one trillion, two hundred seventy-one billion, thirty-four million, four hundred ninety-one thousand, seven hundred eighty".