25661445 has 16 divisors (see below), whose sum is σ = 42844032. Its totient is φ = 13090880.

The previous prime is 25661443. The next prime is 25661453. The reversal of 25661445 is 54416652.

It is not a de Polignac number, because 25661445 - 2¹ = 25661443 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25661443) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 36846 + ... + 37535.

It is an arithmetic number, because the mean of its divisors is an integer number (2677752).

Almost surely, 2^25661445 is an apocalyptic number.

It is an amenable number.

25661445 is a deficient number, since it is larger than the sum of its proper divisors (17182587).

25661445 is a wasteful number, since it uses less digits than its factorization.

25661445 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 74412.

The product of its digits is 28800, while the sum is 33.

The square root of 25661445 is about 5065.7126843121. The cubic root of 25661445 is about 294.9581286928.

It can be divided in two parts, 25661 and 445, that added together give a triangular number (26106 = T₂₂₈).

The spelling of 25661445 in words is "twenty-five million, six hundred sixty-one thousand, four hundred forty-five".