25021221 has 8 divisors (see below), whose sum is σ = 33385344. Its totient is φ = 16668960.

The previous prime is 25021219. The next prime is 25021231. The reversal of 25021221 is 12212052.

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

It is not a de Polignac number, because 25021221 - 2¹ = 25021219 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 25021221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25021231) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5076 + ... + 8706.

It is an arithmetic number, because the mean of its divisors is an integer number (4173168).

Almost surely, 2^25021221 is an apocalyptic number.

It is an amenable number.

25021221 is a deficient number, since it is larger than the sum of its proper divisors (8364123).

25021221 is a wasteful number, since it uses less digits than its factorization.

25021221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5931.

The product of its (nonzero) digits is 80, while the sum is 15.

The square root of 25021221 is about 5002.1216498602. The cubic root of 25021221 is about 292.4844845302.

Adding to 25021221 its reverse (12212052), we get a palindrome (37233273).

The spelling of 25021221 in words is "twenty-five million, twenty-one thousand, two hundred twenty-one".