28228690 has 16 divisors (see below), whose sum is σ = 58070592. Its totient is φ = 9678384.

The previous prime is 28228663. The next prime is 28228691. The reversal of 28228690 is 9682282.

It is a super-2 number, since 2×28228690² = 1593717878232200, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (28228691) 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, 201564 + ... + 201703.

It is an arithmetic number, because the mean of its divisors is an integer number (3629412).

Almost surely, 2^28228690 is an apocalyptic number.

28228690 is an abundant number, since it is smaller than the sum of its proper divisors (29841902).

28228690 is a wasteful number, since it uses less digits than its factorization.

28228690 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 403281.

The product of its (nonzero) digits is 27648, while the sum is 37.

The square root of 28228690 is about 5313.0678520042. The cubic root of 28228690 is about 304.4833679709.

It can be divided in two parts, 282286 and 90, that added together give a triangular number (282376 = T₇₅₁).

The spelling of 28228690 in words is "twenty-eight million, two hundred twenty-eight thousand, six hundred ninety".