21100202121 has 8 divisors (see below), whose sum is σ = 28893970624. Its totient is φ = 13686617520.

The previous prime is 21100202119. The next prime is 21100202131. The reversal of 21100202121 is 12120200112.

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

It is not a de Polignac number, because 21100202121 - 2¹ = 21100202119 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21100202097 and 21100202106.

It is not an unprimeable number, because it can be changed into a prime (21100202131) 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, 95045845 + ... + 95046066.

It is an arithmetic number, because the mean of its divisors is an integer number (3611746328).

Almost surely, 2^21100202121 is an apocalyptic number.

It is an amenable number.

21100202121 is a deficient number, since it is larger than the sum of its proper divisors (7793768503).

21100202121 is a wasteful number, since it uses less digits than its factorization.

21100202121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 190091951.

The product of its (nonzero) digits is 16, while the sum is 12.

Adding to 21100202121 its reverse (12120200112), we get a palindrome (33220402233).

The spelling of 21100202121 in words is "twenty-one billion, one hundred million, two hundred two thousand, one hundred twenty-one".