81728614 has 32 divisors (see below), whose sum is σ = 146914560. Its totient is φ = 33660000.

The previous prime is 81728609. The next prime is 81728653. The reversal of 81728614 is 41682718.

81728614 = 2065² + 2066² + ... + 2083².

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5364 + ... + 13864.

It is an arithmetic number, because the mean of its divisors is an integer number (4591080).

Almost surely, 2^81728614 is an apocalyptic number.

81728614 is a deficient number, since it is larger than the sum of its proper divisors (65185946).

81728614 is a wasteful number, since it uses less digits than its factorization.

81728614 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8556.

The product of its digits is 21504, while the sum is 37.

The square root of 81728614 is about 9040.3879341542. The cubic root of 81728614 is about 433.9683377837.

The spelling of 81728614 in words is "eighty-one million, seven hundred twenty-eight thousand, six hundred fourteen".