21121001202989 has 2 divisors, whose sum is σ = 21121001202990. Its totient is φ = 21121001202988.

The previous prime is 21121001202893. The next prime is 21121001203037. The reversal of 21121001202989 is 98920210012112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18635150754025 + 2485850448964 = 4316845^2 + 1576658^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21121001202989 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21121001202589) 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 as a sum of consecutive naturals, namely, 10560500601494 + 10560500601495.

It is an arithmetic number, because the mean of its divisors is an integer number (10560500601495).

Almost surely, 2^{21121001202989} is an apocalyptic number.

It is an amenable number.

21121001202989 is a deficient number, since it is larger than the sum of its proper divisors (1).

21121001202989 is an equidigital number, since it uses as much as digits as its factorization.

21121001202989 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 10368, while the sum is 38.

The spelling of 21121001202989 in words is "twenty-one trillion, one hundred twenty-one billion, one million, two hundred two thousand, nine hundred eighty-nine".