1318381920 has 336 divisors, whose sum is σ = 4759534080. Its totient is φ = 344881152.

The previous prime is 1318381903. The next prime is 1318381927. The reversal of 1318381920 is 291838131.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1318381927) by changing a digit.

It is a polite number, since it can be written in 55 ways as a sum of consecutive naturals, for example, 10380897 + ... + 10381023.

It is an arithmetic number, because the mean of its divisors is an integer number (14165280).

Almost surely, 2^1318381920 is an apocalyptic number.

1318381920 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 1318381920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2379767040).

1318381920 is an abundant number, since it is smaller than the sum of its proper divisors (3441152160).

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

1318381920 is an equidigital number, since it uses as much as digits as its factorization.

1318381920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 249 (or 226 counting only the distinct ones).

The product of its (nonzero) digits is 10368, while the sum is 36.

The square root of 1318381920 is about 36309.5293277123. The cubic root of 1318381920 is about 1096.5129021745.

The spelling of 1318381920 in words is "one billion, three hundred eighteen million, three hundred eighty-one thousand, nine hundred twenty".