1388438655 has 32 divisors (see below), whose sum is σ = 2332454400. Its totient is φ = 704280192.

The previous prime is 1388438627. The next prime is 1388438657. The reversal of 1388438655 is 5568348831.

It is a happy number.

It is not a de Polignac number, because 1388438655 - 2⁹ = 1388438143 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1388438598 and 1388438607.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1388438657) 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 in 31 ways as a sum of consecutive naturals, for example, 5326 + ... + 52964.

It is an arithmetic number, because the mean of its divisors is an integer number (72889200).

Almost surely, 2^1388438655 is an apocalyptic number.

1388438655 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

1388438655 is a deficient number, since it is larger than the sum of its proper divisors (944015745).

1388438655 is a wasteful number, since it uses less digits than its factorization.

1388438655 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 47743.

The product of its digits is 2764800, while the sum is 51.

The square root of 1388438655 is about 37261.7586138926. The cubic root of 1388438655 is about 1115.6010098804.

The spelling of 1388438655 in words is "one billion, three hundred eighty-eight million, four hundred thirty-eight thousand, six hundred fifty-five".