28972417 has 2 divisors, whose sum is σ = 28972418. Its totient is φ = 28972416.

The previous prime is 28972379. The next prime is 28972423. The reversal of 28972417 is 71427982.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 27133681 + 1838736 = 5209^2 + 1356^2 .

It is a cyclic number.

It is not a de Polignac number, because 28972417 - 2¹⁹ = 28448129 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 28972417.

It is not a weakly prime, because it can be changed into another prime (28972487) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14486208 + 14486209.

It is an arithmetic number, because the mean of its divisors is an integer number (14486209).

Almost surely, 2^28972417 is an apocalyptic number.

It is an amenable number.

28972417 is a deficient number, since it is larger than the sum of its proper divisors (1).

28972417 is an equidigital number, since it uses as much as digits as its factorization.

28972417 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 56448, while the sum is 40.

The square root of 28972417 is about 5382.6031806181. The cubic root of 28972417 is about 307.1342451009.

The spelling of 28972417 in words is "twenty-eight million, nine hundred seventy-two thousand, four hundred seventeen".