2123209987 has 2 divisors, whose sum is σ = 2123209988. Its totient is φ = 2123209986.

The previous prime is 2123209909. The next prime is 2123210039. The reversal of 2123209987 is 7899023212.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 2123209987 - 2¹⁹ = 2122685699 is a prime.

It is not a weakly prime, because it can be changed into another prime (2123209087) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1061604993 + 1061604994.

It is an arithmetic number, because the mean of its divisors is an integer number (1061604994).

Almost surely, 2^2123209987 is an apocalyptic number.

2123209987 is a deficient number, since it is larger than the sum of its proper divisors (1).

2123209987 is an equidigital number, since it uses as much as digits as its factorization.

2123209987 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 108864, while the sum is 43.

The square root of 2123209987 is about 46078.3027790738. The cubic root of 2123209987 is about 1285.2797035304.

The spelling of 2123209987 in words is "two billion, one hundred twenty-three million, two hundred nine thousand, nine hundred eighty-seven".