25665665 has 8 divisors (see below), whose sum is σ = 32610600. Its totient is φ = 19324672.

The previous prime is 25665659. The next prime is 25665671. The reversal of 25665665 is 56656652.

It is an interprime number because it is at equal distance from previous prime (25665659) and next prime (25665671).

It can be written as a sum of positive squares in 4 ways, for example, as 223729 + 25441936 = 473^2 + 5044^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 25665665 - 2¹² = 25661569 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 150890 + ... + 151059.

It is an arithmetic number, because the mean of its divisors is an integer number (4076325).

Almost surely, 2^25665665 is an apocalyptic number.

It is an amenable number.

25665665 is a deficient number, since it is larger than the sum of its proper divisors (6944935).

25665665 is a wasteful number, since it uses less digits than its factorization.

25665665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 301971.

The product of its digits is 324000, while the sum is 41.

The square root of 25665665 is about 5066.1291929835. The cubic root of 25665665 is about 294.9742963337.

The spelling of 25665665 in words is "twenty-five million, six hundred sixty-five thousand, six hundred sixty-five".