81042624 has 168 divisors, whose sum is σ = 255178560. Its totient is φ = 24440832.

The previous prime is 81042613. The next prime is 81042631. The reversal of 81042624 is 42624018.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 591484 + ... + 591620.

It is an arithmetic number, because the mean of its divisors is an integer number (1518920).

Almost surely, 2^81042624 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 81042624, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (127589280).

81042624 is an abundant number, since it is smaller than the sum of its proper divisors (174135936).

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

81042624 is a wasteful number, since it uses less digits than its factorization.

81042624 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 247 (or 234 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 27.

The square root of 81042624 is about 9002.3676885584. The cubic root of 81042624 is about 432.7507521611.

It can be divided in two parts, 810 and 42624, that added together give a palindrome (43434).

The spelling of 81042624 in words is "eighty-one million, forty-two thousand, six hundred twenty-four".