81047488 has 56 divisors (see below), whose sum is σ = 167572944. Its totient is φ = 38860800.

The previous prime is 81047479. The next prime is 81047497. The reversal of 81047488 is 88474018.

It is an interprime number because it is at equal distance from previous prime (81047479) and next prime (81047497).

It is a super-2 number, since 2×81047488² = 13137390622220288, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 81047488.

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 7 ways as a sum of consecutive naturals, for example, 175578 + ... + 176038.

It is an arithmetic number, because the mean of its divisors is an integer number (2992374).

Almost surely, 2^81047488 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 81047488, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (83786472).

81047488 is an abundant number, since it is smaller than the sum of its proper divisors (86525456).

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

81047488 is a wasteful number, since it uses less digits than its factorization.

81047488 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 581 (or 571 counting only the distinct ones).

The product of its (nonzero) digits is 57344, while the sum is 40.

The square root of 81047488 is about 9002.6378356568. The cubic root of 81047488 is about 432.7594095706.

The spelling of 81047488 in words is "eighty-one million, forty-seven thousand, four hundred eighty-eight".