81895264 has 48 divisors (see below), whose sum is σ = 176931216. Its totient is φ = 37004800.

The previous prime is 81895237. The next prime is 81895277. The reversal of 81895264 is 46259818.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 81895264.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 68754 + ... + 69934.

It is an arithmetic number, because the mean of its divisors is an integer number (3686067).

Almost surely, 2^81895264 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 81895264, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (88465608).

81895264 is an abundant number, since it is smaller than the sum of its proper divisors (95035952).

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

81895264 is a wasteful number, since it uses less digits than its factorization.

81895264 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1399 (or 1391 counting only the distinct ones).

The product of its digits is 138240, while the sum is 43.

The square root of 81895264 is about 9049.6002121641. The cubic root of 81895264 is about 434.2631008209.

The spelling of 81895264 in words is "eighty-one million, eight hundred ninety-five thousand, two hundred sixty-four".