81976813376 has 112 divisors (see below), whose sum is σ = 167518226304. Its totient is φ = 39789674496.

The previous prime is 81976813363. The next prime is 81976813409. The reversal of 81976813376 is 67331867918.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 138240536 + ... + 138241128.

Almost surely, 2^81976813376 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81976813376, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (83759113152).

81976813376 is an abundant number, since it is smaller than the sum of its proper divisors (85541412928).

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

81976813376 is a wasteful number, since it uses less digits than its factorization.

81976813376 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1088 (or 1078 counting only the distinct ones).

The product of its digits is 9144576, while the sum is 59.

The spelling of 81976813376 in words is "eighty-one billion, nine hundred seventy-six million, eight hundred thirteen thousand, three hundred seventy-six".