21000121202011 has 16 divisors (see below), whose sum is σ = 24774537553920. Its totient is φ = 17419314032640.

The previous prime is 21000121201987. The next prime is 21000121202023. The reversal of 21000121202011 is 11020212100012.

It is a cyclic number.

It is not a de Polignac number, because 21000121202011 - 2³⁵ = 20965761463643 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21000121201982 and 21000121202000.

It is not an unprimeable number, because it can be changed into a prime (21000121202041) 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, 32904240 + ... + 33536386.

It is an arithmetic number, because the mean of its divisors is an integer number (1548408597120).

Almost surely, 2^{21000121202011} is an apocalyptic number.

21000121202011 is a deficient number, since it is larger than the sum of its proper divisors (3774416351909).

21000121202011 is a wasteful number, since it uses less digits than its factorization.

21000121202011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 785274.

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 21000121202011 its reverse (11020212100012), we get a palindrome (32020333302023).

The spelling of 21000121202011 in words is "twenty-one trillion, one hundred twenty-one million, two hundred two thousand, eleven".