28220623 has 2 divisors, whose sum is σ = 28220624. Its totient is φ = 28220622.

The previous prime is 28220611. The next prime is 28220639. The reversal of 28220623 is 32602282.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28220623 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28220123) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14110311 + 14110312.

It is an arithmetic number, because the mean of its divisors is an integer number (14110312).

Almost surely, 2^28220623 is an apocalyptic number.

28220623 is a deficient number, since it is larger than the sum of its proper divisors (1).

28220623 is an equidigital number, since it uses as much as digits as its factorization.

28220623 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2304, while the sum is 25.

The square root of 28220623 is about 5312.3086318474. The cubic root of 28220623 is about 304.4543608231.

The spelling of 28220623 in words is "twenty-eight million, two hundred twenty thousand, six hundred twenty-three".