28220779 has 2 divisors, whose sum is σ = 28220780. Its totient is φ = 28220778.

The previous prime is 28220761. The next prime is 28220791. The reversal of 28220779 is 97702282.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 28220779 - 2⁷ = 28220651 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (28220579) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14110389 + 14110390.

It is an arithmetic number, because the mean of its divisors is an integer number (14110390).

Almost surely, 2^28220779 is an apocalyptic number.

28220779 is a deficient number, since it is larger than the sum of its proper divisors (1).

28220779 is an equidigital number, since it uses as much as digits as its factorization.

28220779 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 28224, while the sum is 37.

The square root of 28220779 is about 5312.3233147089. The cubic root of 28220779 is about 304.4549218170.

The spelling of 28220779 in words is "twenty-eight million, two hundred twenty thousand, seven hundred seventy-nine".