1381518720 has 256 divisors, whose sum is σ = 5052672000. Its totient is φ = 356382720.

The previous prime is 1381518701. The next prime is 1381518731. The reversal of 1381518720 is 278151831.

1381518720 is a `hidden beast` number, since 138 + 1 + 518 + 7 + 2 + 0 = 666.

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

It is a congruent number.

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 534391 + ... + 536969.

It is an arithmetic number, because the mean of its divisors is an integer number (19737000).

Almost surely, 2^1381518720 is an apocalyptic number.

1381518720 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 1381518720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2526336000).

1381518720 is an abundant number, since it is smaller than the sum of its proper divisors (3671153280).

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

1381518720 is a wasteful number, since it uses less digits than its factorization.

1381518720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2638 (or 2620 counting only the distinct ones).

The product of its (nonzero) digits is 13440, while the sum is 36.

The square root of 1381518720 is about 37168.7869051439. The cubic root of 1381518720 is about 1113.7445487155.

The spelling of 1381518720 in words is "one billion, three hundred eighty-one million, five hundred eighteen thousand, seven hundred twenty".