1386256217 has 4 divisors (see below), whose sum is σ = 1395560100. Its totient is φ = 1376952336.

The previous prime is 1386256199. The next prime is 1386256219. The reversal of 1386256217 is 7126526831.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 7126526831 = 4409 ⋅1616359.

It can be written as a sum of positive squares in 2 ways, for example, as 133379401 + 1252876816 = 11549^2 + 35396^2 .

It is a cyclic number.

It is not a de Polignac number, because 1386256217 - 2¹² = 1386252121 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1386256219) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4651718 + ... + 4652015.

It is an arithmetic number, because the mean of its divisors is an integer number (348890025).

Almost surely, 2^1386256217 is an apocalyptic number.

It is an amenable number.

1386256217 is a deficient number, since it is larger than the sum of its proper divisors (9303883).

1386256217 is an equidigital number, since it uses as much as digits as its factorization.

1386256217 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9303882.

The product of its digits is 120960, while the sum is 41.

The square root of 1386256217 is about 37232.4618713294. The cubic root of 1386256217 is about 1115.0161786548.

The spelling of 1386256217 in words is "one billion, three hundred eighty-six million, two hundred fifty-six thousand, two hundred seventeen".