28690 has 16 divisors (see below), whose sum is σ = 54720. Its totient is φ = 10800.

The previous prime is 28687. The next prime is 28697. The reversal of 28690 is 9682.

It is a super-2 number, since 2×28690² = 1646232200, which contains 22 as substring.

It is a nialpdrome in base 14.

It is not an unprimeable number, because it can be changed into a prime (28697) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 115 + ... + 265.

It is an arithmetic number, because the mean of its divisors is an integer number (3420).

2²⁸⁶⁹⁰ is an apocalyptic number.

28690 is a deficient number, since it is larger than the sum of its proper divisors (26030).

28690 is a wasteful number, since it uses less digits than its factorization.

28690 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 177.

The product of its (nonzero) digits is 864, while the sum is 25.

The square root of 28690 is about 169.3812268228. The cubic root of 28690 is about 30.6133024880.

The spelling of 28690 in words is "twenty-eight thousand, six hundred ninety".