81473663888 has 60 divisors (see below), whose sum is σ = 168798993792. Its totient is φ = 38086310400.

The previous prime is 81473663861. The next prime is 81473663891. The reversal of 81473663888 is 88836637418.

It is a self number, because there is not a number n which added to its sum of digits gives 81473663888.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 639881 + ... + 756567.

Almost surely, 2^81473663888 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 81473663888, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (84399496896).

81473663888 is an abundant number, since it is smaller than the sum of its proper divisors (87325329904).

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

81473663888 is a wasteful number, since it uses less digits than its factorization.

81473663888 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 116880 (or 116857 counting only the distinct ones).

The product of its digits is 37158912, while the sum is 62.

The spelling of 81473663888 in words is "eighty-one billion, four hundred seventy-three million, six hundred sixty-three thousand, eight hundred eighty-eight".