25209649 has 4 divisors (see below), whose sum is σ = 25231360. Its totient is φ = 25187940.

The previous prime is 25209643. The next prime is 25209659. The reversal of 25209649 is 94690252.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 25209649 - 2¹³ = 25201457 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (25209643) 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, 9009 + ... + 11470.

It is an arithmetic number, because the mean of its divisors is an integer number (6307840).

Almost surely, 2^25209649 is an apocalyptic number.

It is an amenable number.

25209649 is a deficient number, since it is larger than the sum of its proper divisors (21711).

25209649 is a wasteful number, since it uses less digits than its factorization.

25209649 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21710.

The product of its (nonzero) digits is 38880, while the sum is 37.

The square root of 25209649 is about 5020.9211306293. The cubic root of 25209649 is about 293.2168561599.

The spelling of 25209649 in words is "twenty-five million, two hundred nine thousand, six hundred forty-nine".