28170979 has 2 divisors, whose sum is σ = 28170980. Its totient is φ = 28170978.

The previous prime is 28170953. The next prime is 28170997. The reversal of 28170979 is 97907182.

It is a happy number.

Together with next prime (28170997) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28170979 is a prime.

It is not a weakly prime, because it can be changed into another prime (28176979) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14085489 + 14085490.

It is an arithmetic number, because the mean of its divisors is an integer number (14085490).

Almost surely, 2^28170979 is an apocalyptic number.

28170979 is a deficient number, since it is larger than the sum of its proper divisors (1).

28170979 is an equidigital number, since it uses as much as digits as its factorization.

28170979 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 63504, while the sum is 43.

The square root of 28170979 is about 5307.6340303378. The cubic root of 28170979 is about 304.2757301849.

The spelling of 28170979 in words is "twenty-eight million, one hundred seventy thousand, nine hundred seventy-nine".