1381824720 has 120 divisors (see below), whose sum is σ = 4706163072. Its totient is φ = 363283200.

The previous prime is 1381824679. The next prime is 1381824727. The reversal of 1381824720 is 274281831.

1381824720 is a `hidden beast` number, since 1 + 3 + 8 + 182 + 472 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (120).

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 (1381824727) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 37605 + ... + 64635.

Almost surely, 2^1381824720 is an apocalyptic number.

1381824720 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 1381824720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2353081536).

1381824720 is an abundant number, since it is smaller than the sum of its proper divisors (3324338352).

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

1381824720 is a wasteful number, since it uses less digits than its factorization.

1381824720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27121 (or 27112 counting only the distinct ones).

The product of its (nonzero) digits is 21504, while the sum is 36.

The square root of 1381824720 is about 37172.9030343340. The cubic root of 1381824720 is about 1113.8267723987.

The spelling of 1381824720 in words is "one billion, three hundred eighty-one million, eight hundred twenty-four thousand, seven hundred twenty".