81023250 has 256 divisors, whose sum is σ = 267411456. Its totient is φ = 15840000.

The previous prime is 81023249. The next prime is 81023279. The reversal of 81023250 is 5232018.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 1328220 + ... + 1328280.

It is an arithmetic number, because the mean of its divisors is an integer number (1044576).

Almost surely, 2^81023250 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81023250, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (133705728).

81023250 is an abundant number, since it is smaller than the sum of its proper divisors (186388206).

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

81023250 is a wasteful number, since it uses less digits than its factorization.

81023250 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 122 (or 112 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 21.

The square root of 81023250 is about 9001.2915739909. The cubic root of 81023250 is about 432.7162650363.

Adding to 81023250 its reverse (5232018), we get a palindrome (86255268).

The spelling of 81023250 in words is "eighty-one million, twenty-three thousand, two hundred fifty".