25124509 has 2 divisors, whose sum is σ = 25124510. Its totient is φ = 25124508.

The previous prime is 25124471. The next prime is 25124549. The reversal of 25124509 is 90542152.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 22829284 + 2295225 = 4778^2 + 1515^2 .

It is a cyclic number.

It is not a de Polignac number, because 25124509 - 2⁷ = 25124381 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25124549) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12562254 + 12562255.

It is an arithmetic number, because the mean of its divisors is an integer number (12562255).

Almost surely, 2^25124509 is an apocalyptic number.

It is an amenable number.

25124509 is a deficient number, since it is larger than the sum of its proper divisors (1).

25124509 is an equidigital number, since it uses as much as digits as its factorization.

25124509 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3600, while the sum is 28.

The square root of 25124509 is about 5012.4354359932. The cubic root of 25124509 is about 292.8863922175.

It can be divided in two parts, 2512 and 4509, that added together give a triangular number (7021 = T₁₁₈).

The spelling of 25124509 in words is "twenty-five million, one hundred twenty-four thousand, five hundred nine".