21715106 has 16 divisors (see below), whose sum is σ = 37329216. Its totient is φ = 9280656.

The previous prime is 21715093. The next prime is 21715153. The reversal of 21715106 is 60151712.

It is an unprimeable number.

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 in 7 ways as a sum of consecutive naturals, for example, 3605 + ... + 7511.

It is an arithmetic number, because the mean of its divisors is an integer number (2333076).

Almost surely, 2^21715106 is an apocalyptic number.

21715106 is a deficient number, since it is larger than the sum of its proper divisors (15614110).

21715106 is a wasteful number, since it uses less digits than its factorization.

21715106 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4313.

The product of its (nonzero) digits is 420, while the sum is 23.

The square root of 21715106 is about 4659.9469954067. The cubic root of 21715106 is about 278.9891526810.

Adding to 21715106 its reverse (60151712), we get a palindrome (81866818).

The spelling of 21715106 in words is "twenty-one million, seven hundred fifteen thousand, one hundred six".