21021120111 has 8 divisors (see below), whose sum is σ = 28040664960. Its totient is φ = 14007827672.

The previous prime is 21021120103. The next prime is 21021120149. The reversal of 21021120111 is 11102112012.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21021120111 - 2³ = 21021120103 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21021120151) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1555251 + ... + 1568708.

It is an arithmetic number, because the mean of its divisors is an integer number (3505083120).

Almost surely, 2^21021120111 is an apocalyptic number.

21021120111 is a deficient number, since it is larger than the sum of its proper divisors (7019544849).

21021120111 is a wasteful number, since it uses less digits than its factorization.

21021120111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3126205.

The product of its (nonzero) digits is 8, while the sum is 12.

Adding to 21021120111 its reverse (11102112012), we get a palindrome (32123232123).

It can be divided in two parts, 2102112011 and 1, that added together give a palindrome (2102112012).

The spelling of 21021120111 in words is "twenty-one billion, twenty-one million, one hundred twenty thousand, one hundred eleven".