81047868 has 24 divisors (see below), whose sum is σ = 206304000. Its totient is φ = 24559920.

The previous prime is 81047867. The next prime is 81047927. The reversal of 81047868 is 86874018.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81047861) by changing a digit.

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, 306868 + ... + 307131.

It is an arithmetic number, because the mean of its divisors is an integer number (8596000).

Almost surely, 2^81047868 is an apocalyptic number.

It is an amenable number.

81047868 is an abundant number, since it is smaller than the sum of its proper divisors (125256132).

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

81047868 is a wasteful number, since it uses less digits than its factorization.

81047868 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 614017 (or 614015 counting only the distinct ones).

The product of its (nonzero) digits is 86016, while the sum is 42.

The square root of 81047868 is about 9002.6589405575. The cubic root of 81047868 is about 432.7600859161.

The spelling of 81047868 in words is "eighty-one million, forty-seven thousand, eight hundred sixty-eight".