25978507 has 4 divisors (see below), whose sum is σ = 26046720. Its totient is φ = 25910296.

The previous prime is 25978501. The next prime is 25978517. The reversal of 25978507 is 70587952.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-25978507 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (25978501) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 33532 + ... + 34297.

It is an arithmetic number, because the mean of its divisors is an integer number (6511680).

Almost surely, 2^25978507 is an apocalyptic number.

25978507 is a deficient number, since it is larger than the sum of its proper divisors (68213).

25978507 is an equidigital number, since it uses as much as digits as its factorization.

25978507 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 68212.

The product of its (nonzero) digits is 176400, while the sum is 43.

The square root of 25978507 is about 5096.9115158103. The cubic root of 25978507 is about 296.1679523776.

The spelling of 25978507 in words is "twenty-five million, nine hundred seventy-eight thousand, five hundred seven".