81733500 has 144 divisors (see below), whose sum is σ = 264727008. Its totient is φ = 21216000.

The previous prime is 81733493. The next prime is 81733507. The reversal of 81733500 is 533718.

It is an interprime number because it is at equal distance from previous prime (81733493) and next prime (81733507).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81733507) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 184279 + ... + 184721.

It is an arithmetic number, because the mean of its divisors is an integer number (1838382).

Almost surely, 2^81733500 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 81733500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (132363504).

81733500 is an abundant number, since it is smaller than the sum of its proper divisors (182993508).

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

81733500 is a wasteful number, since it uses less digits than its factorization.

81733500 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 509 (or 494 counting only the distinct ones).

The product of its (nonzero) digits is 2520, while the sum is 27.

The square root of 81733500 is about 9040.6581618818. The cubic root of 81733500 is about 433.9769856201.

The spelling of 81733500 in words is "eighty-one million, seven hundred thirty-three thousand, five hundred".