2188945920 has 320 divisors, whose sum is σ = 8422318080. Its totient is φ = 473776128.

The previous prime is 2188945909. The next prime is 2188945921. The reversal of 2188945920 is 295498812.

It is a tau number, because it is divible by the number of its divisors (320).

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a self number, because there is not a number n which added to its sum of digits gives 2188945920.

It is not an unprimeable number, because it can be changed into a prime (2188945921) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1020369 + ... + 1022511.

It is an arithmetic number, because the mean of its divisors is an integer number (26319744).

Almost surely, 2^2188945920 is an apocalyptic number.

2188945920 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 2188945920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4211159040).

2188945920 is an abundant number, since it is smaller than the sum of its proper divisors (6233372160).

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

2188945920 is a wasteful number, since it uses less digits than its factorization.

2188945920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2195 (or 2179 counting only the distinct ones).

The product of its (nonzero) digits is 414720, while the sum is 48.

The square root of 2188945920 is about 46786.1723161876. The cubic root of 2188945920 is about 1298.4094788895.

The spelling of 2188945920 in words is "two billion, one hundred eighty-eight million, nine hundred forty-five thousand, nine hundred twenty".