81488568 has 128 divisors (see below), whose sum is σ = 250560000. Its totient is φ = 22014720.

The previous prime is 81488557. The next prime is 81488573. The reversal of 81488568 is 86588418.

It is a Smith number, since the sum of its digits (48) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 156148 + ... + 156668.

It is an arithmetic number, because the mean of its divisors is an integer number (1957500).

Almost surely, 2^81488568 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 81488568, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (125280000).

81488568 is an abundant number, since it is smaller than the sum of its proper divisors (169071432).

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

81488568 is a wasteful number, since it uses less digits than its factorization.

81488568 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 570 (or 552 counting only the distinct ones).

The product of its digits is 491520, while the sum is 48.

The square root of 81488568 is about 9027.1018605087. The cubic root of 81488568 is about 433.5430500995.

The spelling of 81488568 in words is "eighty-one million, four hundred eighty-eight thousand, five hundred sixty-eight".