25555009 has 2 divisors, whose sum is σ = 25555010. Its totient is φ = 25555008.

The previous prime is 25555007. The next prime is 25555031. The reversal of 25555009 is 90055552.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15186609 + 10368400 = 3897^2 + 3220^2 .

It is a cyclic number.

It is not a de Polignac number, because 25555009 - 2¹ = 25555007 is a prime.

Together with 25555007, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (25555007) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12777504 + 12777505.

It is an arithmetic number, because the mean of its divisors is an integer number (12777505).

Almost surely, 2^25555009 is an apocalyptic number.

It is an amenable number.

25555009 is a deficient number, since it is larger than the sum of its proper divisors (1).

25555009 is an equidigital number, since it uses as much as digits as its factorization.

25555009 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 11250, while the sum is 31.

The square root of 25555009 is about 5055.1962375362. The cubic root of 25555009 is about 294.5497642092.

The spelling of 25555009 in words is "twenty-five million, five hundred fifty-five thousand, nine".