121210021987 has 2 divisors, whose sum is σ = 121210021988. Its totient is φ = 121210021986.

The previous prime is 121210021973. The next prime is 121210022029. The reversal of 121210021987 is 789120012121.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 121210021987 - 2³¹ = 119062538339 is a prime.

It is not a weakly prime, because it can be changed into another prime (121210021937) 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, 60605010993 + 60605010994.

It is an arithmetic number, because the mean of its divisors is an integer number (60605010994).

Almost surely, 2^121210021987 is an apocalyptic number.

121210021987 is a deficient number, since it is larger than the sum of its proper divisors (1).

121210021987 is an equidigital number, since it uses as much as digits as its factorization.

121210021987 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4032, while the sum is 34.

The spelling of 121210021987 in words is "one hundred twenty-one billion, two hundred ten million, twenty-one thousand, nine hundred eighty-seven".