21121200120071 has 2 divisors, whose sum is σ = 21121200120072. Its totient is φ = 21121200120070.

The previous prime is 21121200120047. The next prime is 21121200120073. The reversal of 21121200120071 is 17002100212112.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21121200120071 is a prime.

It is a super-2 number, since 2×21121200120071² (a number of 27 digits) contains 22 as substring.

Together with 21121200120073, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21121200120073) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10560600060035 + 10560600060036.

It is an arithmetic number, because the mean of its divisors is an integer number (10560600060036).

Almost surely, 2^{21121200120071} is an apocalyptic number.

21121200120071 is a deficient number, since it is larger than the sum of its proper divisors (1).

21121200120071 is an equidigital number, since it uses as much as digits as its factorization.

21121200120071 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 112, while the sum is 20.

Adding to 21121200120071 its reverse (17002100212112), we get a palindrome (38123300332183).

The spelling of 21121200120071 in words is "twenty-one trillion, one hundred twenty-one billion, two hundred million, one hundred twenty thousand, seventy-one".