1388214640 has 20 divisors (see below), whose sum is σ = 3227599224. Its totient is φ = 555285824.

The previous prime is 1388214617. The next prime is 1388214643. The reversal of 1388214640 is 464128831.

It is a tau number, because it is divible by the number of its divisors (20).

It is a self number, because there is not a number n which added to its sum of digits gives 1388214640.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1388214643) 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 3 ways as a sum of consecutive naturals, for example, 8676262 + ... + 8676421.

Almost surely, 2^1388214640 is an apocalyptic number.

1388214640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1388214640 is an abundant number, since it is smaller than the sum of its proper divisors (1839384584).

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

1388214640 is a wasteful number, since it uses less digits than its factorization.

1388214640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17352696 (or 17352690 counting only the distinct ones).

The product of its (nonzero) digits is 36864, while the sum is 37.

The square root of 1388214640 is about 37258.7525287683. The cubic root of 1388214640 is about 1115.5410084774.

The spelling of 1388214640 in words is "one billion, three hundred eighty-eight million, two hundred fourteen thousand, six hundred forty".