81541792887 has 8 divisors (see below), whose sum is σ = 109719844080. Its totient is φ = 53862468480.

The previous prime is 81541792877. The next prime is 81541792907. The reversal of 81541792887 is 78829714518.

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

It is not a de Polignac number, because 81541792887 - 2¹² = 81541788791 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 81541792887.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81541792877) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 124681314 + ... + 124681967.

It is an arithmetic number, because the mean of its divisors is an integer number (13714980510).

Almost surely, 2^81541792887 is an apocalyptic number.

81541792887 is a deficient number, since it is larger than the sum of its proper divisors (28178051193).

81541792887 is a wasteful number, since it uses less digits than its factorization.

81541792887 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 249363393.

The product of its digits is 9031680, while the sum is 60.

The spelling of 81541792887 in words is "eighty-one billion, five hundred forty-one million, seven hundred ninety-two thousand, eight hundred eighty-seven".