387969139 has 2 divisors, whose sum is σ = 387969140. Its totient is φ = 387969138.

The previous prime is 387969077. The next prime is 387969149. The reversal of 387969139 is 931969783.

It is a strong prime.

It is an emirp because it is prime and its reverse (931969783) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 387969139 - 2¹¹ = 387967091 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 387969139.

It is not a weakly prime, because it can be changed into another prime (387969149) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 193984569 + 193984570.

It is an arithmetic number, because the mean of its divisors is an integer number (193984570).

Almost surely, 2^387969139 is an apocalyptic number.

387969139 is a deficient number, since it is larger than the sum of its proper divisors (1).

387969139 is an equidigital number, since it uses as much as digits as its factorization.

387969139 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2204496, while the sum is 55.

The square root of 387969139 is about 19696.9322230646. The cubic root of 387969139 is about 729.3439649376.

The spelling of 387969139 in words is "three hundred eighty-seven million, nine hundred sixty-nine thousand, one hundred thirty-nine".