1378791918 has 48 divisors (see below), whose sum is σ = 3425157216. Its totient is φ = 392670720.

The previous prime is 1378791917. The next prime is 1378791923. The reversal of 1378791918 is 8191978731.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1378791917) 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 23 ways as a sum of consecutive naturals, for example, 21958 + ... + 56918.

It is an arithmetic number, because the mean of its divisors is an integer number (71357442).

Almost surely, 2^1378791918 is an apocalyptic number.

1378791918 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 1378791918, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1712578608).

1378791918 is an abundant number, since it is smaller than the sum of its proper divisors (2046365298).

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

1378791918 is a wasteful number, since it uses less digits than its factorization.

1378791918 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35289 (or 35286 counting only the distinct ones).

The product of its digits is 762048, while the sum is 54.

The square root of 1378791918 is about 37132.0874446886. The cubic root of 1378791918 is about 1113.0113070780.

The spelling of 1378791918 in words is "one billion, three hundred seventy-eight million, seven hundred ninety-one thousand, nine hundred eighteen".