81292444528 has 20 divisors (see below), whose sum is σ = 165793801960. Its totient is φ = 38506947264.

The previous prime is 81292444523. The next prime is 81292444559. The reversal of 81292444528 is 82544429218.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81292444523) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 133704375 + ... + 133704982.

It is an arithmetic number, because the mean of its divisors is an integer number (8289690098).

Almost surely, 2^81292444528 is an apocalyptic number.

It is an amenable number.

81292444528 is an abundant number, since it is smaller than the sum of its proper divisors (84501357432).

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

81292444528 is a wasteful number, since it uses less digits than its factorization.

81292444528 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 267409384 (or 267409378 counting only the distinct ones).

The product of its digits is 1474560, while the sum is 49.

The spelling of 81292444528 in words is "eighty-one billion, two hundred ninety-two million, four hundred forty-four thousand, five hundred twenty-eight".