81799488 has 168 divisors, whose sum is σ = 249631200. Its totient is φ = 25568256.

The previous prime is 81799463. The next prime is 81799499. The reversal of 81799488 is 88499718.

It is a Smith number, since the sum of its digits (54) coincides with the sum of the digits of its prime factors.

Its product of digits (1161216) is a multiple of the sum of its prime factors (189).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 985495 + ... + 985577.

It is an arithmetic number, because the mean of its divisors is an integer number (1485900).

Almost surely, 2^81799488 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 81799488, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (124815600).

81799488 is an abundant number, since it is smaller than the sum of its proper divisors (167831712).

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

81799488 is a wasteful number, since it uses less digits than its factorization.

81799488 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 189 (or 176 counting only the distinct ones).

The product of its digits is 1161216, while the sum is 54.

The square root of 81799488 is about 9044.3069386217. The cubic root of 81799488 is about 434.0937454553.

The spelling of 81799488 in words is "eighty-one million, seven hundred ninety-nine thousand, four hundred eighty-eight".