81849515487 has 8 divisors (see below), whose sum is σ = 109251442560. Its totient is φ = 54506966040.

The previous prime is 81849515483. The next prime is 81849515497. The reversal of 81849515487 is 78451594818.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 81849515487 - 2² = 81849515483 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 81849515487.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81849515483) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14841189 + ... + 14846702.

It is an arithmetic number, because the mean of its divisors is an integer number (13656430320).

Almost surely, 2^81849515487 is an apocalyptic number.

81849515487 is a deficient number, since it is larger than the sum of its proper divisors (27401927073).

81849515487 is a wasteful number, since it uses less digits than its factorization.

81849515487 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29688813.

The product of its digits is 12902400, while the sum is 60.

The spelling of 81849515487 in words is "eighty-one billion, eight hundred forty-nine million, five hundred fifteen thousand, four hundred eighty-seven".