28666913 has 16 divisors (see below), whose sum is σ = 33929280. Its totient is φ = 23923200.

The previous prime is 28666903. The next prime is 28666919. The reversal of 28666913 is 31966682.

It is a cyclic number.

It is not a de Polignac number, because 28666913 - 2¹⁸ = 28404769 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (41).

It is not an unprimeable number, because it can be changed into a prime (28666919) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5798 + ... + 9536.

It is an arithmetic number, because the mean of its divisors is an integer number (2120580).

Almost surely, 2^28666913 is an apocalyptic number.

It is an amenable number.

28666913 is a deficient number, since it is larger than the sum of its proper divisors (5262367).

28666913 is a wasteful number, since it uses less digits than its factorization.

28666913 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3808.

The product of its digits is 93312, while the sum is 41.

The square root of 28666913 is about 5354.1491387521. The cubic root of 28666913 is about 306.0508872040.

It can be divided in two parts, 286669 and 13, that added together give a palindrome (286682).

The spelling of 28666913 in words is "twenty-eight million, six hundred sixty-six thousand, nine hundred thirteen".