28215023 has 4 divisors (see below), whose sum is σ = 28259280. Its totient is φ = 28170768.

The previous prime is 28215017. The next prime is 28215029. The reversal of 28215023 is 32051282.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (28215017) and next prime (28215029).

It is a cyclic number.

It is not a de Polignac number, because 28215023 - 2⁴ = 28215007 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 28215023.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28215029) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21158 + ... + 22451.

It is an arithmetic number, because the mean of its divisors is an integer number (7064820).

Almost surely, 2^28215023 is an apocalyptic number.

28215023 is a deficient number, since it is larger than the sum of its proper divisors (44257).

28215023 is an equidigital number, since it uses as much as digits as its factorization.

28215023 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44256.

The product of its (nonzero) digits is 960, while the sum is 23.

The square root of 28215023 is about 5311.7815278869. The cubic root of 28215023 is about 304.4342212110.

The spelling of 28215023 in words is "twenty-eight million, two hundred fifteen thousand, twenty-three".