25721089 has 4 divisors (see below), whose sum is σ = 26010180. Its totient is φ = 25432000.

The previous prime is 25721071. The next prime is 25721147. The reversal of 25721089 is 98012752.

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

It can be written as a sum of positive squares in 2 ways, for example, as 8952064 + 16769025 = 2992^2 + 4095^2 .

It is a cyclic number.

It is not a de Polignac number, because 25721089 - 2⁹ = 25720577 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (25721789) 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, 144412 + ... + 144589.

It is an arithmetic number, because the mean of its divisors is an integer number (6502545).

Almost surely, 2^25721089 is an apocalyptic number.

It is an amenable number.

25721089 is a deficient number, since it is larger than the sum of its proper divisors (289091).

25721089 is an equidigital number, since it uses as much as digits as its factorization.

25721089 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 289090.

The product of its (nonzero) digits is 10080, while the sum is 34.

The square root of 25721089 is about 5071.5962970252. The cubic root of 25721089 is about 295.1864721648.

The spelling of 25721089 in words is "twenty-five million, seven hundred twenty-one thousand, eighty-nine".