1388989871 has 2 divisors, whose sum is σ = 1388989872. Its totient is φ = 1388989870.

The previous prime is 1388989867. The next prime is 1388989873. The reversal of 1388989871 is 1789898831.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1388989871 - 2² = 1388989867 is a prime.

Together with 1388989873, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1388989873) 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, 694494935 + 694494936.

It is an arithmetic number, because the mean of its divisors is an integer number (694494936).

Almost surely, 2^1388989871 is an apocalyptic number.

1388989871 is a deficient number, since it is larger than the sum of its proper divisors (1).

1388989871 is an equidigital number, since it uses as much as digits as its factorization.

1388989871 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6967296, while the sum is 62.

The square root of 1388989871 is about 37269.1544175609. The cubic root of 1388989871 is about 1115.7486231160.

The spelling of 1388989871 in words is "one billion, three hundred eighty-eight million, nine hundred eighty-nine thousand, eight hundred seventy-one".