81716628 has 48 divisors (see below), whose sum is σ = 219864960. Its totient is φ = 23138304.

The previous prime is 81716611. The next prime is 81716629. The reversal of 81716628 is 82661718.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81716629) 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, 5188 + ... + 13796.

It is an arithmetic number, because the mean of its divisors is an integer number (4580520).

Almost surely, 2^81716628 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 81716628, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (109932480).

81716628 is an abundant number, since it is smaller than the sum of its proper divisors (138148332).

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

81716628 is a wasteful number, since it uses less digits than its factorization.

81716628 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8736 (or 8734 counting only the distinct ones).

The product of its digits is 32256, while the sum is 39.

The square root of 81716628 is about 9039.7249958171. The cubic root of 81716628 is about 433.9471220449.

The spelling of 81716628 in words is "eighty-one million, seven hundred sixteen thousand, six hundred twenty-eight".