21324536 has 32 divisors (see below), whose sum is σ = 42336000. Its totient is φ = 10041696.

The previous prime is 21324533. The next prime is 21324539. The reversal of 21324536 is 63542312.

It is an interprime number because it is at equal distance from previous prime (21324533) and next prime (21324539).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21324533) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 36035 + ... + 36621.

It is an arithmetic number, because the mean of its divisors is an integer number (1323000).

Almost surely, 2^21324536 is an apocalyptic number.

It is an amenable number.

21324536 is a deficient number, since it is larger than the sum of its proper divisors (21011464).

21324536 is a wasteful number, since it uses less digits than its factorization.

21324536 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 851 (or 847 counting only the distinct ones).

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

The square root of 21324536 is about 4617.8497160475. The cubic root of 21324536 is about 277.3063811846.

Adding to 21324536 its reverse (63542312), we get a palindrome (84866848).

The spelling of 21324536 in words is "twenty-one million, three hundred twenty-four thousand, five hundred thirty-six".