21145232 has 10 divisors (see below), whose sum is σ = 40968918. Its totient is φ = 10572608.

The previous prime is 21145213. The next prime is 21145249. The reversal of 21145232 is 23254112.

It can be written as a sum of positive squares in only one way, i.e., 11806096 + 9339136 = 3436^2 + 3056^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 660773 + ... + 660804.

Almost surely, 2^21145232 is an apocalyptic number.

It is an amenable number.

21145232 is a deficient number, since it is larger than the sum of its proper divisors (19823686).

21145232 is a wasteful number, since it uses less digits than its factorization.

21145232 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1321585 (or 1321579 counting only the distinct ones).

The product of its digits is 480, while the sum is 20.

The square root of 21145232 is about 4598.3945024323. The cubic root of 21145232 is about 276.5269635487.

Adding to 21145232 its reverse (23254112), we get a palindrome (44399344).

The spelling of 21145232 in words is "twenty-one million, one hundred forty-five thousand, two hundred thirty-two".