25670221 has 4 divisors (see below), whose sum is σ = 27180252. Its totient is φ = 24160192.

The previous prime is 25670171. The next prime is 25670243. The reversal of 25670221 is 12207652.

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

It can be written as a sum of positive squares in 2 ways, for example, as 8122500 + 17547721 = 2850^2 + 4189^2 .

It is a cyclic number.

It is not a de Polignac number, because 25670221 - 2¹⁵ = 25637453 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 (25670291) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 754990 + ... + 755023.

It is an arithmetic number, because the mean of its divisors is an integer number (6795063).

Almost surely, 2^25670221 is an apocalyptic number.

It is an amenable number.

25670221 is a deficient number, since it is larger than the sum of its proper divisors (1510031).

25670221 is a wasteful number, since it uses less digits than its factorization.

25670221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1510030.

The product of its (nonzero) digits is 1680, while the sum is 25.

The square root of 25670221 is about 5066.5788259929. The cubic root of 25670221 is about 294.9917492665.

Adding to 25670221 its reverse (12207652), we get a palindrome (37877873).

The spelling of 25670221 in words is "twenty-five million, six hundred seventy thousand, two hundred twenty-one".