21245532 has 48 divisors (see below), whose sum is σ = 61807872. Its totient is φ = 5518080.

The previous prime is 21245531. The next prime is 21245533. The reversal of 21245532 is 23554212.

It is an interprime number because it is at equal distance from previous prime (21245531) and next prime (21245533).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21245531) 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, 10573 + ... + 12420.

It is an arithmetic number, because the mean of its divisors is an integer number (1287664).

Almost surely, 2^21245532 is an apocalyptic number.

21245532 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21245532 is an abundant number, since it is smaller than the sum of its proper divisors (40562340).

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

21245532 is a wasteful number, since it uses less digits than its factorization.

21245532 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23018 (or 23016 counting only the distinct ones).

The product of its digits is 2400, while the sum is 24.

The square root of 21245532 is about 4609.2875805270. The cubic root of 21245532 is about 276.9634987765.

Adding to 21245532 its reverse (23554212), we get a palindrome (44799744).

The spelling of 21245532 in words is "twenty-one million, two hundred forty-five thousand, five hundred thirty-two".