28159222 has 72 divisors (see below), whose sum is σ = 57053808. Its totient is φ = 10311840.

The previous prime is 28159213. The next prime is 28159223. The reversal of 28159222 is 22295182.

It is a Harshad number since it is a multiple of its sum of digits (31).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28159223) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 908347 + ... + 908377.

It is an arithmetic number, because the mean of its divisors is an integer number (792414).

Almost surely, 2^28159222 is an apocalyptic number.

28159222 is an abundant number, since it is smaller than the sum of its proper divisors (28894586).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

28159222 is a wasteful number, since it uses less digits than its factorization.

28159222 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 114 (or 76 counting only the distinct ones).

The product of its digits is 5760, while the sum is 31.

The square root of 28159222 is about 5306.5263591167. The cubic root of 28159222 is about 304.2333950387.

The spelling of 28159222 in words is "twenty-eight million, one hundred fifty-nine thousand, two hundred twenty-two".