1388989872 has 120 divisors (see below), whose sum is σ = 4143020544. Its totient is φ = 433395072.

The previous prime is 1388989871. The next prime is 1388989873. The reversal of 1388989872 is 2789898831.

It is an interprime number because it is at equal distance from previous prime (1388989871) and next prime (1388989873).

It is not an unprimeable number, because it can be changed into a prime (1388989871) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 151203 + ... + 160125.

Almost surely, 2^1388989872 is an apocalyptic number.

1388989872 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1388989872, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2071510272).

1388989872 is an abundant number, since it is smaller than the sum of its proper divisors (2754030672).

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

1388989872 is a wasteful number, since it uses less digits than its factorization.

1388989872 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9007 (or 8998 counting only the distinct ones).

The product of its digits is 13934592, while the sum is 63.

The square root of 1388989872 is about 37269.1544309768. The cubic root of 1388989872 is about 1115.7486233837.

The spelling of 1388989872 in words is "one billion, three hundred eighty-eight million, nine hundred eighty-nine thousand, eight hundred seventy-two".