1605381120 has 660 divisors, whose sum is σ = 6776716320. Its totient is φ = 362299392.

The previous prime is 1605381109. The next prime is 1605381121. The reversal of 1605381120 is 211835061.

1605381120 is a `hidden beast` number, since 1 + 6 + 0 + 538 + 1 + 120 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1605381121) by changing a digit.

It is a polite number, since it can be written in 59 ways as a sum of consecutive naturals, for example, 20321241 + ... + 20321319.

It is an arithmetic number, because the mean of its divisors is an integer number (10267752).

Almost surely, 2^1605381120 is an apocalyptic number.

1605381120 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 1605381120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3388358160).

1605381120 is an abundant number, since it is smaller than the sum of its proper divisors (5171335200).

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

1605381120 is an equidigital number, since it uses as much as digits as its factorization.

1605381120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 130 (or 96 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 27.

The square root of 1605381120 is about 40067.2075393332. The cubic root of 1605381120 is about 1170.9168356021.

The spelling of 1605381120 in words is "one billion, six hundred five million, three hundred eighty-one thousand, one hundred twenty".