1387631938757 has 4 divisors (see below), whose sum is σ = 1387653001260. Its totient is φ = 1387610876256.

The previous prime is 1387631938733. The next prime is 1387631938783. The reversal of 1387631938757 is 7578391367831.

It is a happy number.

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 154141826881 + 1233490111876 = 392609^2 + 1110626^2 .

It is a cyclic number.

It is not a de Polignac number, because 1387631938757 - 2²⁸ = 1387363503301 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1387631938657) 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, 10432118 + ... + 10564295.

It is an arithmetic number, because the mean of its divisors is an integer number (346913250315).

Almost surely, 2^{1387631938757} is an apocalyptic number.

It is an amenable number.

1387631938757 is a deficient number, since it is larger than the sum of its proper divisors (21062503).

1387631938757 is an equidigital number, since it uses as much as digits as its factorization.

1387631938757 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21062502.

The product of its digits is 160030080, while the sum is 68.

The spelling of 1387631938757 in words is "one trillion, three hundred eighty-seven billion, six hundred thirty-one million, nine hundred thirty-eight thousand, seven hundred fifty-seven".