28009973 has 2 divisors, whose sum is σ = 28009974. Its totient is φ = 28009972.

The previous prime is 28009951. The next prime is 28009981. The reversal of 28009973 is 37990082.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18037009 + 9972964 = 4247^2 + 3158^2 .

It is a cyclic number.

It is not a de Polignac number, because 28009973 - 2¹⁰ = 28008949 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28009903) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14004986 + 14004987.

It is an arithmetic number, because the mean of its divisors is an integer number (14004987).

Almost surely, 2^28009973 is an apocalyptic number.

It is an amenable number.

28009973 is a deficient number, since it is larger than the sum of its proper divisors (1).

28009973 is an equidigital number, since it uses as much as digits as its factorization.

28009973 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 27216, while the sum is 38.

The square root of 28009973 is about 5292.4448981543. Note that the first 3 decimals coincide. The cubic root of 28009973 is about 303.6949451721.

It can be divided in two parts, 28009 and 973, that added together give a palindrome (28982).

The spelling of 28009973 in words is "twenty-eight million, nine thousand, nine hundred seventy-three".