81680888 has 8 divisors (see below), whose sum is σ = 153151680. Its totient is φ = 40840440.

The previous prime is 81680827. The next prime is 81680899. The reversal of 81680888 is 88808618.

It is a tau number, because it is divible by the number of its divisors (8).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5105048 + ... + 5105063.

It is an arithmetic number, because the mean of its divisors is an integer number (19143960).

Almost surely, 2^81680888 is an apocalyptic number.

It is an amenable number.

81680888 is a deficient number, since it is larger than the sum of its proper divisors (71470792).

81680888 is a wasteful number, since it uses less digits than its factorization.

81680888 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10210117 (or 10210113 counting only the distinct ones).

The product of its (nonzero) digits is 196608, while the sum is 47.

The square root of 81680888 is about 9037.7479495724. The cubic root of 81680888 is about 433.8838483794.

The spelling of 81680888 in words is "eighty-one million, six hundred eighty thousand, eight hundred eighty-eight".