81428528384 has 144 divisors (see below), whose sum is σ = 189696608640. Its totient is φ = 34161254400.

The previous prime is 81428528341. The next prime is 81428528387. The reversal of 81428528384 is 48382582418.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (53).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81428528387) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 62588534 + ... + 62589834.

It is an arithmetic number, because the mean of its divisors is an integer number (1317337560).

Almost surely, 2^81428528384 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 81428528384, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (94848304320).

81428528384 is an abundant number, since it is smaller than the sum of its proper divisors (108268080256).

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

81428528384 is a wasteful number, since it uses less digits than its factorization.

81428528384 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2036 (or 2022 counting only the distinct ones).

The product of its digits is 3932160, while the sum is 53.

The spelling of 81428528384 in words is "eighty-one billion, four hundred twenty-eight million, five hundred twenty-eight thousand, three hundred eighty-four".