81688024 has 16 divisors (see below), whose sum is σ = 167089320. Its totient is φ = 37130880.

The previous prime is 81687997. The next prime is 81688073. The reversal of 81688024 is 42088618.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 464049 + ... + 464224.

Almost surely, 2^81688024 is an apocalyptic number.

It is an amenable number.

81688024 is an abundant number, since it is smaller than the sum of its proper divisors (85401296).

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

81688024 is a wasteful number, since it uses less digits than its factorization.

81688024 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 928290 (or 928286 counting only the distinct ones).

The product of its (nonzero) digits is 24576, while the sum is 37.

The square root of 81688024 is about 9038.1427295656. The cubic root of 81688024 is about 433.8964833423.

The spelling of 81688024 in words is "eighty-one million, six hundred eighty-eight thousand, twenty-four".