21202102202111 has 4 divisors (see below), whose sum is σ = 21252463490424. Its totient is φ = 21151740913800.

The previous prime is 21202102202087. The next prime is 21202102202117. The reversal of 21202102202111 is 11120220120212.

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 21202102202111 - 2¹⁴ = 21202102185727 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21202102202111.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21202102202117) 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, 25180643525 + ... + 25180644366.

It is an arithmetic number, because the mean of its divisors is an integer number (5313115872606).

Almost surely, 2^{21202102202111} is an apocalyptic number.

21202102202111 is a deficient number, since it is larger than the sum of its proper divisors (50361288313).

21202102202111 is an equidigital number, since it uses as much as digits as its factorization.

21202102202111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50361288312.

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 21202102202111 its reverse (11120220120212), we get a palindrome (32322322322323).

The spelling of 21202102202111 in words is "twenty-one trillion, two hundred two billion, one hundred two million, two hundred two thousand, one hundred eleven".