25990643 has 4 divisors (see below), whose sum is σ = 29703600. Its totient is φ = 22277688.

The previous prime is 25990631. The next prime is 25990661. The reversal of 25990643 is 34609952.

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

It is a cyclic number.

It is not a de Polignac number, because 25990643 - 2⁸ = 25990387 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 25990597 and 25990606.

It is not an unprimeable number, because it can be changed into a prime (25990663) 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, 1856468 + ... + 1856481.

It is an arithmetic number, because the mean of its divisors is an integer number (7425900).

Almost surely, 2^25990643 is an apocalyptic number.

25990643 is a deficient number, since it is larger than the sum of its proper divisors (3712957).

25990643 is an equidigital number, since it uses as much as digits as its factorization.

25990643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3712956.

The product of its (nonzero) digits is 58320, while the sum is 38.

The square root of 25990643 is about 5098.1019016885. The cubic root of 25990643 is about 296.2140640180.

The spelling of 25990643 in words is "twenty-five million, nine hundred ninety thousand, six hundred forty-three".