81706616 has 16 divisors (see below), whose sum is σ = 153295800. Its totient is φ = 40827744.

The previous prime is 81706613. The next prime is 81706621. The reversal of 81706616 is 61660718.

It is a Smith number, since the sum of its digits (35) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81706613) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 23690 + ... + 26918.

Almost surely, 2^81706616 is an apocalyptic number.

It is an amenable number.

81706616 is a deficient number, since it is larger than the sum of its proper divisors (71589184).

81706616 is a wasteful number, since it uses less digits than its factorization.

81706616 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6398 (or 6394 counting only the distinct ones).

The product of its (nonzero) digits is 12096, while the sum is 35.

The square root of 81706616 is about 9039.1712009454. The cubic root of 81706616 is about 433.9293987812.

The spelling of 81706616 in words is "eighty-one million, seven hundred six thousand, six hundred sixteen".