21705676 has 24 divisors (see below), whose sum is σ = 40446000. Its totient is φ = 10162944.

The previous prime is 21705667. The next prime is 21705679. The reversal of 21705676 is 67650712.

It is a super-2 number, since 2×21705676² = 942272741233952, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21705679) 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 7 ways as a sum of consecutive naturals, for example, 5160 + ... + 8368.

It is an arithmetic number, because the mean of its divisors is an integer number (1685250).

Almost surely, 2^21705676 is an apocalyptic number.

It is an amenable number.

21705676 is a deficient number, since it is larger than the sum of its proper divisors (18740324).

21705676 is a wasteful number, since it uses less digits than its factorization.

21705676 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3321 (or 3319 counting only the distinct ones).

The product of its (nonzero) digits is 17640, while the sum is 34.

The square root of 21705676 is about 4658.9350714514. The cubic root of 21705676 is about 278.9487622322.

The spelling of 21705676 in words is "twenty-one million, seven hundred five thousand, six hundred seventy-six".