121000000000021 has 8 divisors (see below), whose sum is σ = 121131124191000. Its totient is φ = 120868905861120.

The previous prime is 121000000000007. The next prime is 121000000000057. The reversal of 121000000000021 is 120000000000121.

It can be written as a sum of positive squares in 4 ways, for example, as 39434066919025 + 81565933080996 = 6279655^2 + 9031386^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 121000000000021 - 2¹¹ = 120999999997973 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 120999999999923 and 121000000000013.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121000000000921) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 548715 + ... + 15566023.

It is an arithmetic number, because the mean of its divisors is an integer number (15141390523875).

Almost surely, 2^{121000000000021} is an apocalyptic number.

It is an amenable number.

121000000000021 is a deficient number, since it is larger than the sum of its proper divisors (131124190979).

121000000000021 is a wasteful number, since it uses less digits than its factorization.

121000000000021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15026039.

The product of its (nonzero) digits is 4, while the sum is 7.

Adding to 121000000000021 its reverse (120000000000121), we get a palindrome (241000000000142).

The spelling of 121000000000021 in words is "one hundred twenty-one trillion, twenty-one", and thus it is an aban number.