81243000 has 320 divisors, whose sum is σ = 305791200. Its totient is φ = 20044800.

The previous prime is 81242999. The next prime is 81243013. The reversal of 81243000 is 34218.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 1376971 + ... + 1377029.

Almost surely, 2^81243000 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 81243000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (152895600).

81243000 is an abundant number, since it is smaller than the sum of its proper divisors (224548200).

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

81243000 is a wasteful number, since it uses less digits than its factorization.

81243000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 109 (or 86 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

The square root of 81243000 is about 9013.4898901591. The cubic root of 81243000 is about 433.1071140081.

Adding to 81243000 its reverse (34218), we get a palindrome (81277218).

It can be divided in two parts, 81 and 243000, that multiplied together give a cube (19683000 = 270³).

The spelling of 81243000 in words is "eighty-one million, two hundred forty-three thousand".