25725721 has 8 divisors (see below), whose sum is σ = 29525760. Its totient is φ = 21956928.

The previous prime is 25725673. The next prime is 25725751. The reversal of 25725721 is 12752752.

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

It is not a de Polignac number, because 25725721 - 2⁹ = 25725209 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (25725751) 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, 6016 + ... + 9361.

It is an arithmetic number, because the mean of its divisors is an integer number (3690720).

Almost surely, 2^25725721 is an apocalyptic number.

It is an amenable number.

25725721 is a deficient number, since it is larger than the sum of its proper divisors (3800039).

25725721 is a wasteful number, since it uses less digits than its factorization.

25725721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15623.

The product of its digits is 9800, while the sum is 31.

The square root of 25725721 is about 5072.0529374209. The cubic root of 25725721 is about 295.2041907208.

The spelling of 25725721 in words is "twenty-five million, seven hundred twenty-five thousand, seven hundred twenty-one".