81042336 has 96 divisors (see below), whose sum is σ = 239057280. Its totient is φ = 26707968.

The previous prime is 81042323. The next prime is 81042361. The reversal of 81042336 is 63324018.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (96).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a nialpdrome in base 14.

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, 83325 + ... + 84291.

It is an arithmetic number, because the mean of its divisors is an integer number (2490180).

Almost surely, 2^81042336 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 81042336, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (119528640).

81042336 is an abundant number, since it is smaller than the sum of its proper divisors (158014944).

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

81042336 is a wasteful number, since it uses less digits than its factorization.

81042336 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1083 (or 1069 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 27.

The square root of 81042336 is about 9002.3516927523. The cubic root of 81042336 is about 432.7502395404.

It can be divided in two parts, 8104 and 2336, that added together give a triangular number (10440 = T₁₄₄).

The spelling of 81042336 in words is "eighty-one million, forty-two thousand, three hundred thirty-six".