81491483504 has 20 divisors (see below), whose sum is σ = 157957267320. Its totient is φ = 40728317760.

The previous prime is 81491483503. The next prime is 81491483537. The reversal of 81491483504 is 40538419418.

It is a happy number.

It is a hoax number, since the sum of its digits (47) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81491483503) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1050374 + ... + 1125285.

It is an arithmetic number, because the mean of its divisors is an integer number (7897863366).

Almost surely, 2^81491483504 is an apocalyptic number.

It is an amenable number.

81491483504 is a deficient number, since it is larger than the sum of its proper divisors (76465783816).

81491483504 is a wasteful number, since it uses less digits than its factorization.

81491483504 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2178008 (or 2178002 counting only the distinct ones).

The product of its (nonzero) digits is 552960, while the sum is 47.

The spelling of 81491483504 in words is "eighty-one billion, four hundred ninety-one million, four hundred eighty-three thousand, five hundred four".