25678509 has 8 divisors (see below), whose sum is σ = 35342592. Its totient is φ = 16566720.

The previous prime is 25678501. The next prime is 25678561. The reversal of 25678509 is 90587652.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 25678509 - 2³ = 25678501 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25678501) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 137964 + ... + 138149.

It is an arithmetic number, because the mean of its divisors is an integer number (4417824).

Almost surely, 2^25678509 is an apocalyptic number.

It is an amenable number.

25678509 is a deficient number, since it is larger than the sum of its proper divisors (9664083).

25678509 is a wasteful number, since it uses less digits than its factorization.

25678509 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 276147.

The product of its (nonzero) digits is 151200, while the sum is 42.

The square root of 25678509 is about 5067.3966689021. The cubic root of 25678509 is about 295.0234932932.

The spelling of 25678509 in words is "twenty-five million, six hundred seventy-eight thousand, five hundred nine".