21130232 has 8 divisors (see below), whose sum is σ = 39619200. Its totient is φ = 10565112.

The previous prime is 21130231. The next prime is 21130247. The reversal of 21130232 is 23203112.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (8).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21130231) by changing a digit.

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 as a sum of consecutive naturals, namely, 1320632 + ... + 1320647.

It is an arithmetic number, because the mean of its divisors is an integer number (4952400).

Almost surely, 2^21130232 is an apocalyptic number.

It is an amenable number.

21130232 is a deficient number, since it is larger than the sum of its proper divisors (18488968).

21130232 is a wasteful number, since it uses less digits than its factorization.

21130232 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2641285 (or 2641281 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 14.

The square root of 21130232 is about 4596.7632090418. The cubic root of 21130232 is about 276.4615605357.

Adding to 21130232 its reverse (23203112), we get a palindrome (44333344).

The spelling of 21130232 in words is "twenty-one million, one hundred thirty thousand, two hundred thirty-two".