4001721984 has 192 divisors, whose sum is σ = 12475008000. Its totient is φ = 1223976960.

The previous prime is 4001721973. The next prime is 4001721991. The reversal of 4001721984 is 4891271004.

4001721984 is a `hidden beast` number, since 400 + 172 + 1 + 9 + 84 = 666.

It is a tau number, because it is divible by the number of its divisors (192).

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

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2859717 + ... + 2861115.

It is an arithmetic number, because the mean of its divisors is an integer number (64974000).

Almost surely, 2^4001721984 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 4001721984, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (6237504000).

4001721984 is an abundant number, since it is smaller than the sum of its proper divisors (8473286016).

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

4001721984 is a wasteful number, since it uses less digits than its factorization.

4001721984 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1623 (or 1608 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 36.

The square root of 4001721984 is about 63259.1652173817. The cubic root of 4001721984 is about 1587.6288092229.

Adding to 4001721984 its reverse (4891271004), we get a palindrome (8892992988).

It can be divided in two parts, 40017 and 21984, that added together give a square (62001 = 249²).

The spelling of 4001721984 in words is "four billion, one million, seven hundred twenty-one thousand, nine hundred eighty-four".