1388213988 has 24 divisors (see below), whose sum is σ = 3701904192. Its totient is φ = 396632544.

The previous prime is 1388213977. The next prime is 1388214011. The reversal of 1388213988 is 8893128831.

It is a self number, because there is not a number n which added to its sum of digits gives 1388213988.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8263095 + ... + 8263262.

It is an arithmetic number, because the mean of its divisors is an integer number (154246008).

Almost surely, 2^1388213988 is an apocalyptic number.

It is an amenable number.

1388213988 is an abundant number, since it is smaller than the sum of its proper divisors (2313690204).

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

1388213988 is a wasteful number, since it uses less digits than its factorization.

1388213988 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16526371 (or 16526369 counting only the distinct ones).

The product of its digits is 663552, while the sum is 51.

The square root of 1388213988 is about 37258.7437791453. The cubic root of 1388213988 is about 1115.5408338328.

The spelling of 1388213988 in words is "one billion, three hundred eighty-eight million, two hundred thirteen thousand, nine hundred eighty-eight".