21065452 has 12 divisors (see below), whose sum is σ = 38804920. Its totient is φ = 9978336.

The previous prime is 21065437. The next prime is 21065453. The reversal of 21065452 is 25456012.

It is not an unprimeable number, because it can be changed into a prime (21065453) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 138513 + ... + 138664.

Almost surely, 2^21065452 is an apocalyptic number.

It is an amenable number.

21065452 is a deficient number, since it is larger than the sum of its proper divisors (17739468).

21065452 is a wasteful number, since it uses less digits than its factorization.

21065452 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 277200 (or 277198 counting only the distinct ones).

The product of its (nonzero) digits is 2400, while the sum is 25.

The square root of 21065452 is about 4589.7115377766. The cubic root of 21065452 is about 276.1787506922.

The spelling of 21065452 in words is "twenty-one million, sixty-five thousand, four hundred fifty-two".