3805721280 has 448 divisors, whose sum is σ = 14337792000. Its totient is φ = 947552256.

The previous prime is 3805721239. The next prime is 3805721287. The reversal of 3805721280 is 821275083.

3805721280 is a `hidden beast` number, since 3 + 8 + 0 + 572 + 1 + 2 + 80 = 666.

It is a super-2 number, since 2×3805721280² = 28967028922089676800, which contains 22 as substring.

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

It is not an unprimeable number, because it can be changed into a prime (3805721287) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 15923401 + ... + 15923639.

It is an arithmetic number, because the mean of its divisors is an integer number (32004000).

Almost surely, 2^3805721280 is an apocalyptic number.

3805721280 is a gapful number since it is divisible by the number (30) 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 3805721280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (7168896000).

3805721280 is an abundant number, since it is smaller than the sum of its proper divisors (10532070720).

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

3805721280 is a wasteful number, since it uses less digits than its factorization.

3805721280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 381 (or 365 counting only the distinct ones).

The product of its (nonzero) digits is 26880, while the sum is 36.

The square root of 3805721280 is about 61690.5282843323. The cubic root of 3805721280 is about 1561.2735162867.

The spelling of 3805721280 in words is "three billion, eight hundred five million, seven hundred twenty-one thousand, two hundred eighty".