81606716 has 24 divisors (see below), whose sum is σ = 144664800. Its totient is φ = 40277952.

The previous prime is 81606713. The next prime is 81606731. The reversal of 81606716 is 61760618.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81606713) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 124646 + ... + 125298.

It is an arithmetic number, because the mean of its divisors is an integer number (6027700).

Almost surely, 2^81606716 is an apocalyptic number.

It is an amenable number.

81606716 is a deficient number, since it is larger than the sum of its proper divisors (63058084).

81606716 is a wasteful number, since it uses less digits than its factorization.

81606716 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1013 (or 1011 counting only the distinct ones).

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

The square root of 81606716 is about 9033.6435617086. The cubic root of 81606716 is about 433.7524762404.

The spelling of 81606716 in words is "eighty-one million, six hundred six thousand, seven hundred sixteen".