81235792 has 80 divisors (see below), whose sum is σ = 191505600. Its totient is φ = 32901120.

The previous prime is 81235789. The next prime is 81235829. The reversal of 81235792 is 29753218.

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, 56134 + ... + 57562.

It is an arithmetic number, because the mean of its divisors is an integer number (2393820).

Almost surely, 2^81235792 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 81235792, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (95752800).

81235792 is an abundant number, since it is smaller than the sum of its proper divisors (110269808).

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

81235792 is a wasteful number, since it uses less digits than its factorization.

81235792 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1484 (or 1478 counting only the distinct ones).

The product of its digits is 30240, while the sum is 37.

The square root of 81235792 is about 9013.0900361641. The cubic root of 81235792 is about 433.0943049932.

The spelling of 81235792 in words is "eighty-one million, two hundred thirty-five thousand, seven hundred ninety-two".