81854280 has 128 divisors (see below), whose sum is σ = 287280000. Its totient is φ = 20673792.

The previous prime is 81854273. The next prime is 81854287. The reversal of 81854280 is 8245818.

It is an interprime number because it is at equal distance from previous prime (81854273) and next prime (81854287).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (81854287) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 18526 + ... + 22514.

It is an arithmetic number, because the mean of its divisors is an integer number (2244375).

Almost surely, 2^81854280 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 81854280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (143640000).

81854280 is an abundant number, since it is smaller than the sum of its proper divisors (205425720).

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

81854280 is a wasteful number, since it uses less digits than its factorization.

81854280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4028 (or 4018 counting only the distinct ones).

The product of its (nonzero) digits is 20480, while the sum is 36.

The square root of 81854280 is about 9047.3355193670. The cubic root of 81854280 is about 434.1906472674.

The spelling of 81854280 in words is "eighty-one million, eight hundred fifty-four thousand, two hundred eighty".