21232641 has 16 divisors (see below), whose sum is σ = 28831680. Its totient is φ = 13896960.

The previous prime is 21232639. The next prime is 21232663. The reversal of 21232641 is 14623212.

It is not a de Polignac number, because 21232641 - 2¹ = 21232639 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21232681) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 74886 + ... + 75168.

It is an arithmetic number, because the mean of its divisors is an integer number (1801980).

Almost surely, 2^21232641 is an apocalyptic number.

It is an amenable number.

21232641 is a deficient number, since it is larger than the sum of its proper divisors (7599039).

21232641 is a wasteful number, since it uses less digits than its factorization.

21232641 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 656.

The product of its digits is 576, while the sum is 21.

The square root of 21232641 is about 4607.8889960588. Note that the first 3 decimals coincide. The cubic root of 21232641 is about 276.9074703871.

Adding to 21232641 its reverse (14623212), we get a palindrome (35855853).

The spelling of 21232641 in words is "twenty-one million, two hundred thirty-two thousand, six hundred forty-one".