28223997 has 8 divisors (see below), whose sum is σ = 37779456. Its totient is φ = 18742272.

The previous prime is 28223941. The next prime is 28224011. The reversal of 28223997 is 79932282.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 28223997 - 2⁷ = 28223869 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28223197) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17533 + ... + 19074.

It is an arithmetic number, because the mean of its divisors is an integer number (4722432).

Almost surely, 2^28223997 is an apocalyptic number.

It is an amenable number.

28223997 is a deficient number, since it is larger than the sum of its proper divisors (9555459).

28223997 is a wasteful number, since it uses less digits than its factorization.

28223997 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36867.

The product of its digits is 108864, while the sum is 42.

The square root of 28223997 is about 5312.6261867367. The cubic root of 28223997 is about 304.4664936533.

The spelling of 28223997 in words is "twenty-eight million, two hundred twenty-three thousand, nine hundred ninety-seven".