21710671 has 4 divisors (see below), whose sum is σ = 21742344. Its totient is φ = 21679000.

The previous prime is 21710669. The next prime is 21710687. The reversal of 21710671 is 17601712.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21710671 - 2¹ = 21710669 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21710371) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 14785 + ... + 16186.

It is an arithmetic number, because the mean of its divisors is an integer number (5435586).

Almost surely, 2^21710671 is an apocalyptic number.

21710671 is a deficient number, since it is larger than the sum of its proper divisors (31673).

21710671 is an equidigital number, since it uses as much as digits as its factorization.

21710671 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31672.

The product of its (nonzero) digits is 588, while the sum is 25.

The square root of 21710671 is about 4659.4711073254. The cubic root of 21710671 is about 278.9701582056.

The spelling of 21710671 in words is "twenty-one million, seven hundred ten thousand, six hundred seventy-one".