81090024 has 64 divisors (see below), whose sum is σ = 216192000. Its totient is φ = 25272000.

The previous prime is 81090011. The next prime is 81090041. The reversal of 81090024 is 42009018.

It is a Cunningham number, because it is equal to 9005²-1.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a junction number, because it is equal to n+sod(n) for n = 81089976 and 81090003.

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, 34899 + ... + 37149.

It is an arithmetic number, because the mean of its divisors is an integer number (3378000).

Almost surely, 2^81090024 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 81090024, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (108096000).

81090024 is an abundant number, since it is smaller than the sum of its proper divisors (135101976).

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

81090024 is a wasteful number, since it uses less digits than its factorization.

81090024 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2358 (or 2354 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 24.

The square root of 81090024 is about 9004.9999444753. Note that the first 4 decimals coincide. The cubic root of 81090024 is about 432.8351044309.

The spelling of 81090024 in words is "eighty-one million, ninety thousand, twenty-four".