1388814915 has 32 divisors (see below), whose sum is σ = 2397231936. Its totient is φ = 683970560.

The previous prime is 1388814821. The next prime is 1388814923. The reversal of 1388814915 is 5194188831.

It is a happy number.

It is not a de Polignac number, because 1388814915 - 2⁹ = 1388814403 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 37866 + ... + 64895.

It is an arithmetic number, because the mean of its divisors is an integer number (74913498).

Almost surely, 2^1388814915 is an apocalyptic number.

1388814915 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

1388814915 is a deficient number, since it is larger than the sum of its proper divisors (1008417021).

1388814915 is a wasteful number, since it uses less digits than its factorization.

1388814915 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 102839.

The product of its digits is 276480, while the sum is 48.

The square root of 1388814915 is about 37266.8071479165. The cubic root of 1388814915 is about 1115.7017748951.

The spelling of 1388814915 in words is "one billion, three hundred eighty-eight million, eight hundred fourteen thousand, nine hundred fifteen".