21136711 has 4 divisors (see below), whose sum is σ = 21188800. Its totient is φ = 21084624.

The previous prime is 21136681. The next prime is 21136723. The reversal of 21136711 is 11763112.

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 21136711 - 2²³ = 12748103 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 (21136751) 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, 25431 + ... + 26248.

It is an arithmetic number, because the mean of its divisors is an integer number (5297200).

Almost surely, 2^21136711 is an apocalyptic number.

21136711 is a deficient number, since it is larger than the sum of its proper divisors (52089).

21136711 is an equidigital number, since it uses as much as digits as its factorization.

21136711 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52088.

The product of its digits is 252, while the sum is 22.

The square root of 21136711 is about 4597.4678900456. The cubic root of 21136711 is about 276.4898140732.

Adding to 21136711 its reverse (11763112), we get a palindrome (32899823).

The spelling of 21136711 in words is "twenty-one million, one hundred thirty-six thousand, seven hundred eleven".