1387376665 has 4 divisors (see below), whose sum is σ = 1664852004. Its totient is φ = 1109901328.

The previous prime is 1387376663. The next prime is 1387376677. The reversal of 1387376665 is 5666737831.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 800380681 + 586995984 = 28291^2 + 24228^2 .

It is a cyclic number.

It is not a de Polignac number, because 1387376665 - 2¹ = 1387376663 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1387376663) 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 in 3 ways as a sum of consecutive naturals, for example, 138737662 + ... + 138737671.

It is an arithmetic number, because the mean of its divisors is an integer number (416213001).

Almost surely, 2^1387376665 is an apocalyptic number.

It is an amenable number.

1387376665 is a deficient number, since it is larger than the sum of its proper divisors (277475339).

1387376665 is an equidigital number, since it uses as much as digits as its factorization.

1387376665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 277475338.

The product of its digits is 3810240, while the sum is 52.

The square root of 1387376665 is about 37247.5054869450. The cubic root of 1387376665 is about 1115.3165034178.

The spelling of 1387376665 in words is "one billion, three hundred eighty-seven million, three hundred seventy-six thousand, six hundred sixty-five".