28220423 has 24 divisors (see below), whose sum is σ = 36714384. Its totient is φ = 21436800.

The previous prime is 28220419. The next prime is 28220431. The reversal of 28220423 is 32402282.

It is not a de Polignac number, because 28220423 - 2² = 28220419 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28220443) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 21461 + ... + 22737.

It is an arithmetic number, because the mean of its divisors is an integer number (1529766).

Almost surely, 2^28220423 is an apocalyptic number.

28220423 is a deficient number, since it is larger than the sum of its proper divisors (8493961).

28220423 is a wasteful number, since it uses less digits than its factorization.

28220423 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1343 (or 1336 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 23.

The square root of 28220423 is about 5312.2898076065. The cubic root of 28220423 is about 304.4536415972.

The spelling of 28220423 in words is "twenty-eight million, two hundred twenty thousand, four hundred twenty-three".