21424246211 has 4 divisors (see below), whose sum is σ = 21775463424. Its totient is φ = 21073029000.

The previous prime is 21424246177. The next prime is 21424246253. The reversal of 21424246211 is 11264242412.

It is a happy number.

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-21424246211 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21424246111) 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, 175608515 + ... + 175608636.

It is an arithmetic number, because the mean of its divisors is an integer number (5443865856).

Almost surely, 2^21424246211 is an apocalyptic number.

21424246211 is a deficient number, since it is larger than the sum of its proper divisors (351217213).

21424246211 is an equidigital number, since it uses as much as digits as its factorization.

21424246211 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 351217212.

The product of its digits is 6144, while the sum is 29.

Adding to 21424246211 its reverse (11264242412), we get a palindrome (32688488623).

The spelling of 21424246211 in words is "twenty-one billion, four hundred twenty-four million, two hundred forty-six thousand, two hundred eleven".