121000000000921 has 2 divisors, whose sum is σ = 121000000000922. Its totient is φ = 121000000000920.

The previous prime is 121000000000907. The next prime is 121000000000951. The reversal of 121000000000921 is 129000000000121.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 61944156352521 + 59055843648400 = 7870461^2 + 7684780^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-121000000000921 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 121000000000895 and 121000000000904.

It is not a weakly prime, because it can be changed into another prime (121000000000951) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60500000000460 + 60500000000461.

It is an arithmetic number, because the mean of its divisors is an integer number (60500000000461).

Almost surely, 2^{121000000000921} is an apocalyptic number.

It is an amenable number.

121000000000921 is a deficient number, since it is larger than the sum of its proper divisors (1).

121000000000921 is an equidigital number, since it uses as much as digits as its factorization.

121000000000921 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 36, while the sum is 16.

The spelling of 121000000000921 in words is "one hundred twenty-one trillion, nine hundred twenty-one", and thus it is an aban number.