1721985888 has 96 divisors (see below), whose sum is σ = 5206892544. Its totient is φ = 488097792.

The previous prime is 1721985871. The next prime is 1721985929. The reversal of 1721985888 is 8885891271.

It is a tau number, because it is divible by the number of its divisors (96).

It is a super-2 number, since 2×1721985888² = 5930470796942297088, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 75256 + ... + 95432.

It is an arithmetic number, because the mean of its divisors is an integer number (54238464).

Almost surely, 2^1721985888 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 1721985888, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2603446272).

1721985888 is an abundant number, since it is smaller than the sum of its proper divisors (3484906656).

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

1721985888 is a wasteful number, since it uses less digits than its factorization.

1721985888 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20324 (or 20316 counting only the distinct ones).

The product of its digits is 2580480, while the sum is 57.

The square root of 1721985888 is about 41496.8178057065. The cubic root of 1721985888 is about 1198.6062262334.

The spelling of 1721985888 in words is "one billion, seven hundred twenty-one million, nine hundred eighty-five thousand, eight hundred eighty-eight".