21021121011121 has 16 divisors (see below), whose sum is σ = 27587527234560. Its totient is φ = 15517984067280.

The previous prime is 21021121011113. The next prime is 21021121011157. The reversal of 21021121011121 is 12111012112012.

It is a cyclic number.

It is not a de Polignac number, because 21021121011121 - 2³ = 21021121011113 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21021121011095 and 21021121011104.

It is not an unprimeable number, because it can be changed into a prime (21021121014121) 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, 7184250421 + ... + 7184253346.

It is an arithmetic number, because the mean of its divisors is an integer number (1724220452160).

Almost surely, 2^{21021121011121} is an apocalyptic number.

It is an amenable number.

21021121011121 is a deficient number, since it is larger than the sum of its proper divisors (6566406223439).

21021121011121 is a wasteful number, since it uses less digits than its factorization.

21021121011121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14368503804.

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

Adding to 21021121011121 its reverse (12111012112012), we get a palindrome (33132133123133).

The spelling of 21021121011121 in words is "twenty-one trillion, twenty-one billion, one hundred twenty-one million, eleven thousand, one hundred twenty-one".