2121012021823 has 2 divisors, whose sum is σ = 2121012021824. Its totient is φ = 2121012021822.

The previous prime is 2121012021743. The next prime is 2121012021827. The reversal of 2121012021823 is 3281202101212.

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-2121012021823 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2121012021827) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1060506010911 + 1060506010912.

It is an arithmetic number, because the mean of its divisors is an integer number (1060506010912).

Almost surely, 2^{2121012021823} is an apocalyptic number.

2121012021823 is a deficient number, since it is larger than the sum of its proper divisors (1).

2121012021823 is an equidigital number, since it uses as much as digits as its factorization.

2121012021823 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 768, while the sum is 25.

The spelling of 2121012021823 in words is "two trillion, one hundred twenty-one billion, twelve million, twenty-one thousand, eight hundred twenty-three".