21203252 has 12 divisors (see below), whose sum is σ = 42406560. Its totient is φ = 9087096.

The previous prime is 21203249. The next prime is 21203279. The reversal of 21203252 is 25230212.

21203252 is an admirable number.

21203252 is a modest number, since divided by 3252 gives 212 as remainder.

It is a self number, because there is not a number n which added to its sum of digits gives 21203252.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 378602 + ... + 378657.

It is an arithmetic number, because the mean of its divisors is an integer number (3533880).

Almost surely, 2^21203252 is an apocalyptic number.

It is an amenable number.

21203252 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

21203252 is a wasteful number, since it uses less digits than its factorization.

21203252 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 757270 (or 757268 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 17.

The square root of 21203252 is about 4604.6989043802. The cubic root of 21203252 is about 276.7796515998.

Adding to 21203252 its reverse (25230212), we get a palindrome (46433464).

The spelling of 21203252 in words is "twenty-one million, two hundred three thousand, two hundred fifty-two".