25828991 has 4 divisors (see below), whose sum is σ = 26378592. Its totient is φ = 25279392.

The previous prime is 25828981. The next prime is 25828993. The reversal of 25828991 is 19982852.

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 25828991 - 2⁶ = 25828927 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25828993) 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, 274730 + ... + 274823.

It is an arithmetic number, because the mean of its divisors is an integer number (6594648).

Almost surely, 2^25828991 is an apocalyptic number.

25828991 is a deficient number, since it is larger than the sum of its proper divisors (549601).

25828991 is an equidigital number, since it uses as much as digits as its factorization.

25828991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 549600.

The product of its digits is 103680, while the sum is 44.

The square root of 25828991 is about 5082.2230372151. The cubic root of 25828991 is about 295.5986731513.

The spelling of 25828991 in words is "twenty-five million, eight hundred twenty-eight thousand, nine hundred ninety-one".