28688651 has 4 divisors (see below), whose sum is σ = 30198600. Its totient is φ = 27178704.

The previous prime is 28688633. The next prime is 28688677. The reversal of 28688651 is 15688682.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 15688682 = 2 ⋅7844341.

It is a cyclic number.

It is not a de Polignac number, because 28688651 - 2⁶ = 28688587 is a prime.

It is not an unprimeable number, because it can be changed into a prime (28684651) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 754946 + ... + 754983.

It is an arithmetic number, because the mean of its divisors is an integer number (7549650).

Almost surely, 2^28688651 is an apocalyptic number.

28688651 is a deficient number, since it is larger than the sum of its proper divisors (1509949).

28688651 is a wasteful number, since it uses less digits than its factorization.

28688651 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1509948.

The product of its digits is 184320, while the sum is 44.

The square root of 28688651 is about 5356.1787684878. The cubic root of 28688651 is about 306.1282266936.

The spelling of 28688651 in words is "twenty-eight million, six hundred eighty-eight thousand, six hundred fifty-one".