387997121 has 2 divisors, whose sum is σ = 387997122. Its totient is φ = 387997120.

The previous prime is 387997109. The next prime is 387997123. The reversal of 387997121 is 121799783.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 256000000 + 131997121 = 16000^2 + 11489^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-387997121 is a prime.

It is a Sophie Germain prime.

Together with 387997123, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (387997123) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 193998560 + 193998561.

It is an arithmetic number, because the mean of its divisors is an integer number (193998561).

Almost surely, 2^387997121 is an apocalyptic number.

It is an amenable number.

387997121 is a deficient number, since it is larger than the sum of its proper divisors (1).

387997121 is an equidigital number, since it uses as much as digits as its factorization.

387997121 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 190512, while the sum is 47.

The square root of 387997121 is about 19697.6425239164. The cubic root of 387997121 is about 729.3614989888.

The spelling of 387997121 in words is "three hundred eighty-seven million, nine hundred ninety-seven thousand, one hundred twenty-one".