21100001021121 has 16 divisors (see below), whose sum is σ = 30737341637568. Its totient is φ = 12768533131200.

The previous prime is 21100001021069. The next prime is 21100001021123. The reversal of 21100001021121 is 12112010000112.

It is not a de Polignac number, because 21100001021121 - 2¹⁷ = 21100000890049 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21100001021097 and 21100001021106.

It is not an unprimeable number, because it can be changed into a prime (21100001021123) 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, 483634746 + ... + 483678371.

It is an arithmetic number, because the mean of its divisors is an integer number (1921083852348).

Almost surely, 2^{21100001021121} is an apocalyptic number.

It is an amenable number.

21100001021121 is a deficient number, since it is larger than the sum of its proper divisors (9637340616447).

21100001021121 is a wasteful number, since it uses less digits than its factorization.

21100001021121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 967313792.

The product of its (nonzero) digits is 8, while the sum is 12.

Adding to 21100001021121 its reverse (12112010000112), we get a palindrome (33212011021233).

The spelling of 21100001021121 in words is "twenty-one trillion, one hundred billion, one million, twenty-one thousand, one hundred twenty-one".