21701711 has 4 divisors (see below), whose sum is σ = 21788424. Its totient is φ = 21615000.

The previous prime is 21701689. The next prime is 21701723. The reversal of 21701711 is 11710712.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21701711 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 (21701731) 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, 42980 + ... + 43481.

It is an arithmetic number, because the mean of its divisors is an integer number (5447106).

Almost surely, 2^21701711 is an apocalyptic number.

21701711 is a deficient number, since it is larger than the sum of its proper divisors (86713).

21701711 is an equidigital number, since it uses as much as digits as its factorization.

21701711 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 86712.

The product of its (nonzero) digits is 98, while the sum is 20.

The square root of 21701711 is about 4658.5095255886. The cubic root of 21701711 is about 278.9317759042.

Subtracting from 21701711 its reverse (11710712), we obtain a palindrome (9990999).

The spelling of 21701711 in words is "twenty-one million, seven hundred one thousand, seven hundred eleven".