21200111210121 has 8 divisors (see below), whose sum is σ = 28266843051264. Its totient is φ = 14133393421200.

The previous prime is 21200111210107. The next prime is 21200111210129. The reversal of 21200111210121 is 12101211100212.

It is a happy number.

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

It is not a de Polignac number, because 21200111210121 - 2⁹ = 21200111209609 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21200111210121.

It is not an unprimeable number, because it can be changed into a prime (21200111210129) 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, 744175 + ... + 6553931.

It is an arithmetic number, because the mean of its divisors is an integer number (3533355381408).

Almost surely, 2^{21200111210121} is an apocalyptic number.

It is an amenable number.

21200111210121 is a deficient number, since it is larger than the sum of its proper divisors (7066731841143).

21200111210121 is a wasteful number, since it uses less digits than its factorization.

21200111210121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7026111.

The product of its (nonzero) digits is 16, while the sum is 15.

Adding to 21200111210121 its reverse (12101211100212), we get a palindrome (33301322310333).

The spelling of 21200111210121 in words is "twenty-one trillion, two hundred billion, one hundred eleven million, two hundred ten thousand, one hundred twenty-one".