1388128900 has 18 divisors (see below), whose sum is σ = 3012239930. Its totient is φ = 555251520.

The previous prime is 1388128891. The next prime is 1388128909. The reversal of 1388128900 is 98218831.

It is an interprime number because it is at equal distance from previous prime (1388128891) and next prime (1388128909).

It can be written as a sum of positive squares in 3 ways, for example, as 2502724 + 1385626176 = 1582^2 + 37224^2 .

It is not an unprimeable number, because it can be changed into a prime (1388128909) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 6940545 + ... + 6940744.

Almost surely, 2^1388128900 is an apocalyptic number.

1388128900 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1388128900 is an abundant number, since it is smaller than the sum of its proper divisors (1624111030).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1388128900 is a wasteful number, since it uses less digits than its factorization.

1388128900 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13881303 (or 13881296 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 40.

The square root of 1388128900 is about 37257.6019088722. The cubic root of 1388128900 is about 1115.5180416987.

The spelling of 1388128900 in words is "one billion, three hundred eighty-eight million, one hundred twenty-eight thousand, nine hundred".