21149536 has 12 divisors (see below), whose sum is σ = 41638212. Its totient is φ = 10574752.

The previous prime is 21149509. The next prime is 21149539. The reversal of 21149536 is 63594112.

It is a junction number, because it is equal to n+sod(n) for n = 21149498 and 21149507.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21149539) 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 as a sum of consecutive naturals, namely, 330430 + ... + 330493.

It is an arithmetic number, because the mean of its divisors is an integer number (3469851).

Almost surely, 2^21149536 is an apocalyptic number.

It is an amenable number.

21149536 is a deficient number, since it is larger than the sum of its proper divisors (20488676).

21149536 is an equidigital number, since it uses as much as digits as its factorization.

21149536 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 660933 (or 660925 counting only the distinct ones).

The product of its digits is 6480, while the sum is 31.

The square root of 21149536 is about 4598.8624680458. The cubic root of 21149536 is about 276.5457241423.

The spelling of 21149536 in words is "twenty-one million, one hundred forty-nine thousand, five hundred thirty-six".