1389968640 has 288 divisors, whose sum is σ = 5070428160. Its totient is φ = 360308736.

The previous prime is 1389968621. The next prime is 1389968641. The reversal of 1389968640 is 468699831.

It is a tau number, because it is divible by the number of its divisors (288).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1389968641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1278177 + ... + 1279263.

Almost surely, 2^1389968640 is an apocalyptic number.

1389968640 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 1389968640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2535214080).

1389968640 is an abundant number, since it is smaller than the sum of its proper divisors (3680459520).

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

1389968640 is a wasteful number, since it uses less digits than its factorization.

1389968640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1154 (or 1134 counting only the distinct ones).

The product of its (nonzero) digits is 2239488, while the sum is 54.

The square root of 1389968640 is about 37282.2831918862. The cubic root of 1389968640 is about 1116.0106369665.

The spelling of 1389968640 in words is "one billion, three hundred eighty-nine million, nine hundred sixty-eight thousand, six hundred forty".