121110000000021 has 24 divisors (see below), whose sum is σ = 175265141157080. Its totient is φ = 80588490264576.

The previous prime is 121109999999993. The next prime is 121110000000047. The reversal of 121110000000021 is 120000000011121.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 35422375788900 + 85687624211121 = 5951670^2 + 9256761^2 .

It is not a de Polignac number, because 121110000000021 - 2⁷ = 121109999999893 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 121109999999940 and 121110000000012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121110000050021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 11577885 + ... + 19397613.

Almost surely, 2^{121110000000021} is an apocalyptic number.

It is an amenable number.

121110000000021 is a deficient number, since it is larger than the sum of its proper divisors (54155141157059).

121110000000021 is a wasteful number, since it uses less digits than its factorization.

121110000000021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7822965 (or 7822962 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 9.

Adding to 121110000000021 its reverse (120000000011121), we get a palindrome (241110000011142).

The spelling of 121110000000021 in words is "one hundred twenty-one trillion, one hundred ten billion, twenty-one", and thus it is an aban number.