28209890 has 16 divisors (see below), whose sum is σ = 50984640. Its totient is φ = 11238000.

The previous prime is 28209829. The next prime is 28209893. The reversal of 28209890 is 9890282.

It is not an unprimeable number, because it can be changed into a prime (28209893) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3110 + ... + 8129.

It is an arithmetic number, because the mean of its divisors is an integer number (3186540).

Almost surely, 2^28209890 is an apocalyptic number.

28209890 is a deficient number, since it is larger than the sum of its proper divisors (22774750).

28209890 is a wasteful number, since it uses less digits than its factorization.

28209890 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11497.

The product of its (nonzero) digits is 20736, while the sum is 38.

The square root of 28209890 is about 5311.2983346824. The cubic root of 28209890 is about 304.4157587577.

The spelling of 28209890 in words is "twenty-eight million, two hundred nine thousand, eight hundred ninety".