21710406 has 16 divisors (see below), whose sum is σ = 43504704. Its totient is φ = 7222824.

The previous prime is 21710389. The next prime is 21710417. The reversal of 21710406 is 60401712.

It is a Curzon number.

It is a congruent number.

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, 165 + ... + 6591.

It is an arithmetic number, because the mean of its divisors is an integer number (2719044).

Almost surely, 2^21710406 is an apocalyptic number.

21710406 is an abundant number, since it is smaller than the sum of its proper divisors (21794298).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21710406 is a wasteful number, since it uses less digits than its factorization.

21710406 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6995.

The product of its (nonzero) digits is 336, while the sum is 21.

The square root of 21710406 is about 4659.4426705347. The cubic root of 21710406 is about 278.9690231663.

The spelling of 21710406 in words is "twenty-one million, seven hundred ten thousand, four hundred six".