28775623 has 4 divisors (see below), whose sum is σ = 28798128. Its totient is φ = 28753120.

The previous prime is 28775597. The next prime is 28775653. The reversal of 28775623 is 32657782.

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

It is a cyclic number.

It is not a de Polignac number, because 28775623 - 2²¹ = 26678471 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28775653) 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, 9211 + ... + 11932.

It is an arithmetic number, because the mean of its divisors is an integer number (7199532).

Almost surely, 2^28775623 is an apocalyptic number.

28775623 is a deficient number, since it is larger than the sum of its proper divisors (22505).

28775623 is a wasteful number, since it uses less digits than its factorization.

28775623 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22504.

The product of its digits is 141120, while the sum is 40.

The square root of 28775623 is about 5364.2914723195. The cubic root of 28775623 is about 306.4372655593.

The spelling of 28775623 in words is "twenty-eight million, seven hundred seventy-five thousand, six hundred twenty-three".