21220311011 has 16 divisors (see below), whose sum is σ = 21922787328. Its totient is φ = 20531988000.

The previous prime is 21220310999. The next prime is 21220311041. The reversal of 21220311011 is 11011302212.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21220311011 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21220311041) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 937550 + ... + 959916.

It is an arithmetic number, because the mean of its divisors is an integer number (1370174208).

Almost surely, 2^21220311011 is an apocalyptic number.

21220311011 is a deficient number, since it is larger than the sum of its proper divisors (702476317).

21220311011 is a wasteful number, since it uses less digits than its factorization.

21220311011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22682.

The product of its (nonzero) digits is 24, while the sum is 14.

Adding to 21220311011 its reverse (11011302212), we get a palindrome (32231613223).

The spelling of 21220311011 in words is "twenty-one billion, two hundred twenty million, three hundred eleven thousand, eleven".