81838746 has 48 divisors (see below), whose sum is σ = 198682848. Its totient is φ = 24127200.

The previous prime is 81838741. The next prime is 81838751. The reversal of 81838746 is 64783818.

It is an interprime number because it is at equal distance from previous prime (81838741) and next prime (81838751).

It is not an unprimeable number, because it can be changed into a prime (81838741) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1741 + ... + 12911.

It is an arithmetic number, because the mean of its divisors is an integer number (4139226).

Almost surely, 2^81838746 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81838746, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (99341424).

81838746 is an abundant number, since it is smaller than the sum of its proper divisors (116844102).

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

81838746 is a wasteful number, since it uses less digits than its factorization.

81838746 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11227 (or 11224 counting only the distinct ones).

The product of its digits is 258048, while the sum is 45.

The square root of 81838746 is about 9046.4769938358. The cubic root of 81838746 is about 434.1631791691.

The spelling of 81838746 in words is "eighty-one million, eight hundred thirty-eight thousand, seven hundred forty-six".