21102200121 has 16 divisors (see below), whose sum is σ = 29056384448. Its totient is φ = 13612276800.

The previous prime is 21102200069. The next prime is 21102200143. The reversal of 21102200121 is 12100220112.

It is not a de Polignac number, because 21102200121 - 2¹⁸ = 21101937977 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21102200097 and 21102200106.

It is not an unprimeable number, because it can be changed into a prime (21102200621) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 505075 + ... + 545256.

It is an arithmetic number, because the mean of its divisors is an integer number (1816024028).

Almost surely, 2^21102200121 is an apocalyptic number.

It is an amenable number.

21102200121 is a deficient number, since it is larger than the sum of its proper divisors (7954184327).

21102200121 is a wasteful number, since it uses less digits than its factorization.

21102200121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1050552.

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

Adding to 21102200121 its reverse (12100220112), we get a palindrome (33202420233).

The spelling of 21102200121 in words is "twenty-one billion, one hundred two million, two hundred thousand, one hundred twenty-one".