25721212 has 36 divisors (see below), whose sum is σ = 52098760. Its totient is φ = 11072160.

The previous prime is 25721203. The next prime is 25721239. The reversal of 25721212 is 21212752.

It is a Harshad number since it is a multiple of its sum of digits (22).

It is a congruent number.

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 7798 + ... + 10594.

Almost surely, 2^25721212 is an apocalyptic number.

25721212 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

25721212 is an abundant number, since it is smaller than the sum of its proper divisors (26377548).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

25721212 is a wasteful number, since it uses less digits than its factorization.

25721212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2842 (or 2829 counting only the distinct ones).

The product of its digits is 560, while the sum is 22.

The square root of 25721212 is about 5071.6084233702. The cubic root of 25721212 is about 295.1869426979.

Adding to 25721212 its reverse (21212752), we get a palindrome (46933964).

The spelling of 25721212 in words is "twenty-five million, seven hundred twenty-one thousand, two hundred twelve".