1721181852 has 144 divisors (see below), whose sum is σ = 4868004960. Its totient is φ = 525657600.

The previous prime is 1721181841. The next prime is 1721181863. The reversal of 1721181852 is 2581811271.

It is an interprime number because it is at equal distance from previous prime (1721181841) and next prime (1721181863).

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 3303352 + ... + 3303872.

It is an arithmetic number, because the mean of its divisors is an integer number (33805590).

Almost surely, 2^1721181852 is an apocalyptic number.

1721181852 is a gapful number since it is divisible by the number (12) 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 1721181852, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2434002480).

1721181852 is an abundant number, since it is smaller than the sum of its proper divisors (3146823108).

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

1721181852 is a wasteful number, since it uses less digits than its factorization.

1721181852 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 741 (or 720 counting only the distinct ones).

The product of its digits is 8960, while the sum is 36.

The square root of 1721181852 is about 41487.1287509753. The cubic root of 1721181852 is about 1198.4196446444.

The spelling of 1721181852 in words is "one billion, seven hundred twenty-one million, one hundred eighty-one thousand, eight hundred fifty-two".