21705452 has 6 divisors (see below), whose sum is σ = 37984548. Its totient is φ = 10852724.

The previous prime is 21705433. The next prime is 21705469. The reversal of 21705452 is 25450712.

It is a super-2 number, since 2×21705452² = 942253293048608, which contains 22 as substring.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 2713178 + ... + 2713185.

It is an arithmetic number, because the mean of its divisors is an integer number (6330758).

Almost surely, 2^21705452 is an apocalyptic number.

It is an amenable number.

21705452 is a deficient number, since it is larger than the sum of its proper divisors (16279096).

21705452 is a wasteful number, since it uses less digits than its factorization.

21705452 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5426367 (or 5426365 counting only the distinct ones).

The product of its (nonzero) digits is 2800, while the sum is 26.

The square root of 21705452 is about 4658.9110315609. The cubic root of 21705452 is about 278.9478026562.

The spelling of 21705452 in words is "twenty-one million, seven hundred five thousand, four hundred fifty-two".