121001111021 has 12 divisors (see below), whose sum is σ = 149036183388. Its totient is φ = 97614340992.

The previous prime is 121001110973. The next prime is 121001111029. The reversal of 121001111021 is 120111100121.

It can be written as a sum of positive squares in 2 ways, for example, as 102941514025 + 18059596996 = 320845^2 + 134386^2 .

It is a de Polignac number, because none of the positive numbers 2^k-121001111021 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 121001110993 and 121001111011.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121001111029) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 72628886 + ... + 72630551.

It is an arithmetic number, because the mean of its divisors is an integer number (12419681949).

Almost surely, 2^121001111021 is an apocalyptic number.

It is an amenable number.

121001111021 is a deficient number, since it is larger than the sum of its proper divisors (28035072367).

121001111021 is a wasteful number, since it uses less digits than its factorization.

121001111021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 145259468 (or 145259461 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 11.

Adding to 121001111021 its reverse (120111100121), we get a palindrome (241112211142).

The spelling of 121001111021 in words is "one hundred twenty-one billion, one million, one hundred eleven thousand, twenty-one".