81424200 has 288 divisors, whose sum is σ = 302257440. Its totient is φ = 17971200.

The previous prime is 81424153. The next prime is 81424201. The reversal of 81424200 is 242418.

It is not an unprimeable number, because it can be changed into a prime (81424201) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 1115364 + ... + 1115436.

It is an arithmetic number, because the mean of its divisors is an integer number (1049505).

Almost surely, 2^81424200 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 81424200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (151128720).

81424200 is an abundant number, since it is smaller than the sum of its proper divisors (220833240).

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

81424200 is a wasteful number, since it uses less digits than its factorization.

81424200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 129 (or 107 counting only the distinct ones).

The product of its (nonzero) digits is 512, while the sum is 21.

The square root of 81424200 is about 9023.5358923207. The cubic root of 81424200 is about 433.4288678254.

Adding to 81424200 its reverse (242418), we get a palindrome (81666618).

The spelling of 81424200 in words is "eighty-one million, four hundred twenty-four thousand, two hundred".