81757676 has 72 divisors (see below), whose sum is σ = 195599376. Its totient is φ = 29393280.

The previous prime is 81757673. The next prime is 81757717. The reversal of 81757676 is 67675718.

It is a self number, because there is not a number n which added to its sum of digits gives 81757676.

It is not an unprimeable number, because it can be changed into a prime (81757673) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 26570 + ... + 29486.

It is an arithmetic number, because the mean of its divisors is an integer number (2716658).

Almost surely, 2^81757676 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 81757676, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (97799688).

81757676 is an abundant number, since it is smaller than the sum of its proper divisors (113841700).

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

81757676 is a wasteful number, since it uses less digits than its factorization.

81757676 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2959 (or 2950 counting only the distinct ones).

The product of its digits is 493920, while the sum is 47.

The square root of 81757676 is about 9041.9951338186. The cubic root of 81757676 is about 434.0197701712.

It can be divided in two parts, 8175 and 7676, that added together give a palindrome (15851).

The spelling of 81757676 in words is "eighty-one million, seven hundred fifty-seven thousand, six hundred seventy-six".