81240124 has 48 divisors (see below), whose sum is σ = 173286400. Its totient is φ = 32550336.

The previous prime is 81240101. The next prime is 81240139. The reversal of 81240124 is 42104218.

It is a junction number, because it is equal to n+sod(n) for n = 81240095 and 81240104.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 41062 + ... + 42994.

Almost surely, 2^81240124 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 81240124, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (86643200).

81240124 is an abundant number, since it is smaller than the sum of its proper divisors (92046276).

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

81240124 is a wasteful number, since it uses less digits than its factorization.

81240124 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2042 (or 2040 counting only the distinct ones).

The product of its (nonzero) digits is 512, while the sum is 22.

The square root of 81240124 is about 9013.3303500981. The cubic root of 81240124 is about 433.1020032878.

The spelling of 81240124 in words is "eighty-one million, two hundred forty thousand, one hundred twenty-four".