28025009 has 2 divisors, whose sum is σ = 28025010. Its totient is φ = 28025008.

The previous prime is 28024999. The next prime is 28025029. The reversal of 28025009 is 90052082.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 24403600 + 3621409 = 4940^2 + 1903^2 .

It is a cyclic number.

It is not a de Polignac number, because 28025009 - 2¹⁶ = 27959473 is a prime.

It is a super-2 number, since 2×28025009² = 1570802258900162, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (28025029) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14012504 + 14012505.

It is an arithmetic number, because the mean of its divisors is an integer number (14012505).

Almost surely, 2^28025009 is an apocalyptic number.

It is an amenable number.

28025009 is a deficient number, since it is larger than the sum of its proper divisors (1).

28025009 is an equidigital number, since it uses as much as digits as its factorization.

28025009 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1440, while the sum is 26.

The square root of 28025009 is about 5293.8652230672. The cubic root of 28025009 is about 303.7492774910.

The spelling of 28025009 in words is "twenty-eight million, twenty-five thousand, nine".