2179643840 has 112 divisors (see below), whose sum is σ = 5686982784. Its totient is φ = 789120000.

The previous prime is 2179643789. The next prime is 2179643861. The reversal of 2179643840 is 483469712.

It is a Harshad number since it is a multiple of its sum of digits (44).

It is a junction number, because it is equal to n+sod(n) for n = 2179643791 and 2179643800.

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, 882287 + ... + 884753.

It is an arithmetic number, because the mean of its divisors is an integer number (50776632).

Almost surely, 2^2179643840 is an apocalyptic number.

2179643840 is a gapful number since it is divisible by the number (20) 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 2179643840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2843491392).

2179643840 is an abundant number, since it is smaller than the sum of its proper divisors (3507338944).

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

2179643840 is a wasteful number, since it uses less digits than its factorization.

2179643840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2746 (or 2736 counting only the distinct ones).

The product of its (nonzero) digits is 290304, while the sum is 44.

The square root of 2179643840 is about 46686.6559093709. The cubic root of 2179643840 is about 1296.5676398742.

The spelling of 2179643840 in words is "two billion, one hundred seventy-nine million, six hundred forty-three thousand, eight hundred forty".