81897576 has 32 divisors (see below), whose sum is σ = 210279840. Its totient is φ = 26561088.

The previous prime is 81897523. The next prime is 81897583. The reversal of 81897576 is 67579818.

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 7 ways as a sum of consecutive naturals, for example, 45226 + ... + 47001.

It is an arithmetic number, because the mean of its divisors is an integer number (6571245).

Almost surely, 2^81897576 is an apocalyptic number.

It is an amenable number.

81897576 is an abundant number, since it is smaller than the sum of its proper divisors (128382264).

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

81897576 is a wasteful number, since it uses less digits than its factorization.

81897576 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 92273 (or 92269 counting only the distinct ones).

The product of its digits is 846720, while the sum is 51.

The square root of 81897576 is about 9049.7279517121. The cubic root of 81897576 is about 434.2671873692.

The spelling of 81897576 in words is "eighty-one million, eight hundred ninety-seven thousand, five hundred seventy-six".