87728 has 10 divisors (see below), whose sum is σ = 170004. Its totient is φ = 43856.

The previous prime is 87721. The next prime is 87739. The reversal of 87728 is 82778.

It is a happy number.

It is an Ulam number.

It is a junction number, because it is equal to n+sod(n) for n = 87694 and 87703.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 87728.

It is not an unprimeable number, because it can be changed into a prime (87721) by changing a digit.

87728 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2726 + ... + 2757.

2⁸⁷⁷²⁸ is an apocalyptic number.

It is an amenable number.

87728 is a deficient number, since it is larger than the sum of its proper divisors (82276).

87728 is a wasteful number, since it uses less digits than its factorization.

87728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5491 (or 5485 counting only the distinct ones).

The product of its digits is 6272, while the sum is 32.

The square root of 87728 is about 296.1891287674. The cubic root of 87728 is about 44.4337270454.

Subtracting from 87728 its reverse (82778), we obtain a triangular number (4950 = T₉₉).

It can be divided in two parts, 87 and 728, that multiplied together give a palindrome (63336).

The spelling of 87728 in words is "eighty-seven thousand, seven hundred twenty-eight".