21715066011 has 4 divisors (see below), whose sum is σ = 28953421352. Its totient is φ = 14476710672.

The previous prime is 21715065973. The next prime is 21715066019. The reversal of 21715066011 is 11066051712.

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

It is not a de Polignac number, because 21715066011 - 2⁹ = 21715065499 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21715066011.

It is not an unprimeable number, because it can be changed into a prime (21715066019) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3619177666 + ... + 3619177671.

It is an arithmetic number, because the mean of its divisors is an integer number (7238355338).

Almost surely, 2^21715066011 is an apocalyptic number.

21715066011 is a deficient number, since it is larger than the sum of its proper divisors (7238355341).

21715066011 is an equidigital number, since it uses as much as digits as its factorization.

21715066011 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7238355340.

The product of its (nonzero) digits is 2520, while the sum is 30.

The spelling of 21715066011 in words is "twenty-one billion, seven hundred fifteen million, sixty-six thousand, eleven".