2161850780 has 48 divisors (see below), whose sum is σ = 4796820000. Its totient is φ = 816143616.

The previous prime is 2161850771. The next prime is 2161850807. The reversal of 2161850780 is 870581612.

It is a Harshad number since it is a multiple of its sum of digits (38).

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, 91646 + ... + 112794.

It is an arithmetic number, because the mean of its divisors is an integer number (99933750).

Almost surely, 2^2161850780 is an apocalyptic number.

2161850780 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 2161850780, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2398410000).

2161850780 is an abundant number, since it is smaller than the sum of its proper divisors (2634969220).

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

2161850780 is a wasteful number, since it uses less digits than its factorization.

2161850780 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21446 (or 21444 counting only the distinct ones).

The product of its (nonzero) digits is 26880, while the sum is 38.

The square root of 2161850780 is about 46495.7071136680. The cubic root of 2161850780 is about 1293.0299109010.

The spelling of 2161850780 in words is "two billion, one hundred sixty-one million, eight hundred fifty thousand, seven hundred eighty".