81897676 has 48 divisors (see below), whose sum is σ = 173376000. Its totient is φ = 33067008.

The previous prime is 81897661. The next prime is 81897679. The reversal of 81897676 is 67679818.

It is not an unprimeable number, because it can be changed into a prime (81897679) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 136425 + ... + 137023.

It is an arithmetic number, because the mean of its divisors is an integer number (3612000).

Almost surely, 2^81897676 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 81897676, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (86688000).

81897676 is an abundant number, since it is smaller than the sum of its proper divisors (91478324).

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

81897676 is a wasteful number, since it uses less digits than its factorization.

81897676 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 886 (or 884 counting only the distinct ones).

The product of its digits is 1016064, while the sum is 52.

The square root of 81897676 is about 9049.7334767384. The cubic root of 81897676 is about 434.2673641213.

The spelling of 81897676 in words is "eighty-one million, eight hundred ninety-seven thousand, six hundred seventy-six".