25042221 has 6 divisors (see below), whose sum is σ = 36172110. Its totient is φ = 16694808.

The previous prime is 25042189. The next prime is 25042223. The reversal of 25042221 is 12224052.

It can be written as a sum of positive squares in only one way, i.e., 24890121 + 152100 = 4989^2 + 390^2 .

It is not a de Polignac number, because 25042221 - 2⁵ = 25042189 is a prime.

It is a super-2 number, since 2×25042221² = 1254225665225682, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 25042194 and 25042203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25042223) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1391226 + ... + 1391243.

It is an arithmetic number, because the mean of its divisors is an integer number (6028685).

Almost surely, 2^25042221 is an apocalyptic number.

It is an amenable number.

25042221 is a deficient number, since it is larger than the sum of its proper divisors (11129889).

25042221 is a wasteful number, since it uses less digits than its factorization.

25042221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2782475 (or 2782472 counting only the distinct ones).

The product of its (nonzero) digits is 320, while the sum is 18.

The square root of 25042221 is about 5004.2203188908. The cubic root of 25042221 is about 292.5662878473.

Adding to 25042221 its reverse (12224052), we get a palindrome (37266273).

The spelling of 25042221 in words is "twenty-five million, forty-two thousand, two hundred twenty-one".