1378439040 has 128 divisors (see below), whose sum is σ = 4793281920. Its totient is φ = 334161920.

The previous prime is 1378438993. The next prime is 1378439047. The reversal of 1378439040 is 409348731.

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

It is a super-2 number, since 2×1378439040² = 3800188373992243200, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1378439040.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1378439047) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 11514 + ... + 53753.

It is an arithmetic number, because the mean of its divisors is an integer number (37447515).

Almost surely, 2^1378439040 is an apocalyptic number.

1378439040 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 1378439040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2396640960).

1378439040 is an abundant number, since it is smaller than the sum of its proper divisors (3414842880).

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

1378439040 is a wasteful number, since it uses less digits than its factorization.

1378439040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 65300 (or 65288 counting only the distinct ones).

The product of its (nonzero) digits is 72576, while the sum is 39.

The square root of 1378439040 is about 37127.3354820946. The cubic root of 1378439040 is about 1112.9163469635.

The spelling of 1378439040 in words is "one billion, three hundred seventy-eight million, four hundred thirty-nine thousand, forty".