81443250 has 96 divisors (see below), whose sum is σ = 251731584. Its totient is φ = 18612000.

The previous prime is 81443249. The next prime is 81443267. The reversal of 81443250 is 5234418.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 13165 + ... + 18335.

It is an arithmetic number, because the mean of its divisors is an integer number (2622204).

Almost surely, 2^81443250 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81443250, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (125865792).

81443250 is an abundant number, since it is smaller than the sum of its proper divisors (170288334).

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

81443250 is a wasteful number, since it uses less digits than its factorization.

81443250 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5201 (or 5188 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 27.

The square root of 81443250 is about 9024.5914034930. The cubic root of 81443250 is about 433.4626668520.

Adding to 81443250 its reverse (5234418), we get a palindrome (86677668).

The spelling of 81443250 in words is "eighty-one million, four hundred forty-three thousand, two hundred fifty".