1393888640 has 128 divisors (see below), whose sum is σ = 3554496000. Its totient is φ = 521164800.

The previous prime is 1393888609. The next prime is 1393888649. The reversal of 1393888640 is 468883931.

It is a tau number, because it is divible by the number of its divisors (128).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1393888649) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 959915 + ... + 961365.

It is an arithmetic number, because the mean of its divisors is an integer number (27769500).

Almost surely, 2^1393888640 is an apocalyptic number.

1393888640 is a gapful number since it is divisible by the number (10) 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 1393888640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1777248000).

1393888640 is an abundant number, since it is smaller than the sum of its proper divisors (2160607360).

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

1393888640 is a wasteful number, since it uses less digits than its factorization.

1393888640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1568 (or 1556 counting only the distinct ones).

The product of its (nonzero) digits is 995328, while the sum is 50.

The square root of 1393888640 is about 37334.8180657145. The cubic root of 1393888640 is about 1117.0587794507.

The spelling of 1393888640 in words is "one billion, three hundred ninety-three million, eight hundred eighty-eight thousand, six hundred forty".