2121123311947 has 2 divisors, whose sum is σ = 2121123311948. Its totient is φ = 2121123311946.

The previous prime is 2121123311927. The next prime is 2121123312097. The reversal of 2121123311947 is 7491133211212.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2121123311947 is a prime.

It is not a weakly prime, because it can be changed into another prime (2121123311927) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1060561655973 + 1060561655974.

It is an arithmetic number, because the mean of its divisors is an integer number (1060561655974).

Almost surely, 2^{2121123311947} is an apocalyptic number.

2121123311947 is a deficient number, since it is larger than the sum of its proper divisors (1).

2121123311947 is an equidigital number, since it uses as much as digits as its factorization.

2121123311947 is an evil number, because the sum of its binary digits is even.

The product of its digits is 18144, while the sum is 37.

The spelling of 2121123311947 in words is "two trillion, one hundred twenty-one billion, one hundred twenty-three million, three hundred eleven thousand, nine hundred forty-seven".