21232253 has 16 divisors (see below), whose sum is σ = 25681920. Its totient is φ = 17147376.

The previous prime is 21232249. The next prime is 21232259. The reversal of 21232253 is 35223212.

It is a cyclic number.

It is not a de Polignac number, because 21232253 - 2² = 21232249 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21232259) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 34676 + ... + 35282.

It is an arithmetic number, because the mean of its divisors is an integer number (1605120).

Almost surely, 2^21232253 is an apocalyptic number.

It is an amenable number.

21232253 is a deficient number, since it is larger than the sum of its proper divisors (4449667).

21232253 is a wasteful number, since it uses less digits than its factorization.

21232253 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 896.

The product of its digits is 720, while the sum is 20.

The square root of 21232253 is about 4607.8468941578. The cubic root of 21232253 is about 276.9057836641.

Adding to 21232253 its reverse (35223212), we get a palindrome (56455465).

The spelling of 21232253 in words is "twenty-one million, two hundred thirty-two thousand, two hundred fifty-three".