21001214111 has 4 divisors (see below), whose sum is σ = 21001940400. Its totient is φ = 21000487824.

The previous prime is 21001214077. The next prime is 21001214123. The reversal of 21001214111 is 11141210012.

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 21001214111 - 2¹⁴ = 21001197727 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 (21001214161) 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, 317891 + ... + 378228.

It is an arithmetic number, because the mean of its divisors is an integer number (5250485100).

Almost surely, 2^21001214111 is an apocalyptic number.

21001214111 is a deficient number, since it is larger than the sum of its proper divisors (726289).

21001214111 is an equidigital number, since it uses as much as digits as its factorization.

21001214111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 726288.

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 21001214111 its reverse (11141210012), we get a palindrome (32142424123).

The spelling of 21001214111 in words is "twenty-one billion, one million, two hundred fourteen thousand, one hundred eleven".