1871721120 has 96 divisors (see below), whose sum is σ = 5918088960. Its totient is φ = 497249280.

The previous prime is 1871721083. The next prime is 1871721121. The reversal of 1871721120 is 211271781.

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

It is a Harshad number since it is a multiple of its sum of digits (30).

It is not an unprimeable number, because it can be changed into a prime (1871721121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 122886 + ... + 137274.

It is an arithmetic number, because the mean of its divisors is an integer number (61646760).

Almost surely, 2^1871721120 is an apocalyptic number.

1871721120 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 1871721120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2959044480).

1871721120 is an abundant number, since it is smaller than the sum of its proper divisors (4046367840).

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

1871721120 is a wasteful number, since it uses less digits than its factorization.

1871721120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14678 (or 14670 counting only the distinct ones).

The product of its (nonzero) digits is 1568, while the sum is 30.

The square root of 1871721120 is about 43263.3923773899. The cubic root of 1871721120 is about 1232.3868254587.

The spelling of 1871721120 in words is "one billion, eight hundred seventy-one million, seven hundred twenty-one thousand, one hundred twenty".