21001202120111 has 8 divisors (see below), whose sum is σ = 21121491726720. Its totient is φ = 20880945452248.

The previous prime is 21001202120099. The next prime is 21001202120123. The reversal of 21001202120111 is 11102120210012.

It is an interprime number because it is at equal distance from previous prime (21001202120099) and next prime (21001202120123).

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21001202120111 is a prime.

It is a super-2 number, since 2×21001202120111² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21001202120411) 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, 6955301 + ... + 9506766.

It is an arithmetic number, because the mean of its divisors is an integer number (2640186465840).

Almost surely, 2^{21001202120111} is an apocalyptic number.

21001202120111 is a deficient number, since it is larger than the sum of its proper divisors (120289606609).

21001202120111 is a wasteful number, since it uses less digits than its factorization.

21001202120111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16469373.

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

Adding to 21001202120111 its reverse (11102120210012), we get a palindrome (32103322330123).

The spelling of 21001202120111 in words is "twenty-one trillion, one billion, two hundred two million, one hundred twenty thousand, one hundred eleven".