21345632 has 48 divisors (see below), whose sum is σ = 52399872. Its totient is φ = 8315520.

The previous prime is 21345629. The next prime is 21345637. The reversal of 21345632 is 23654312.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21345637) 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 7 ways as a sum of consecutive naturals, for example, 1868 + ... + 6795.

It is an arithmetic number, because the mean of its divisors is an integer number (1091664).

Almost surely, 2^21345632 is an apocalyptic number.

21345632 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21345632 is an abundant number, since it is smaller than the sum of its proper divisors (31054240).

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

21345632 is a wasteful number, since it uses less digits than its factorization.

21345632 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8691 (or 8683 counting only the distinct ones).

The product of its digits is 4320, while the sum is 26.

The square root of 21345632 is about 4620.1333314094. The cubic root of 21345632 is about 277.3977958717.

Adding to 21345632 its reverse (23654312), we get a palindrome (44999944).

The spelling of 21345632 in words is "twenty-one million, three hundred forty-five thousand, six hundred thirty-two".