25665951 has 4 divisors (see below), whose sum is σ = 34221272. Its totient is φ = 17110632.

The previous prime is 25665949. The next prime is 25665961. The reversal of 25665951 is 15956652.

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

It is not a de Polignac number, because 25665951 - 2¹ = 25665949 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 (25665911) 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, 4277656 + ... + 4277661.

It is an arithmetic number, because the mean of its divisors is an integer number (8555318).

Almost surely, 2^25665951 is an apocalyptic number.

25665951 is a deficient number, since it is larger than the sum of its proper divisors (8555321).

25665951 is an equidigital number, since it uses as much as digits as its factorization.

25665951 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8555320.

The product of its digits is 81000, while the sum is 39.

The square root of 25665951 is about 5066.1574195834. The cubic root of 25665951 is about 294.9753919912.

The spelling of 25665951 in words is "twenty-five million, six hundred sixty-five thousand, nine hundred fifty-one".