2188420640 has 96 divisors (see below), whose sum is σ = 5925104640. Its totient is φ = 748237824.

The previous prime is 2188420621. The next prime is 2188420651. The reversal of 2188420640 is 460248812.

It is a Harshad number since it is a multiple of its sum of digits (35).

It is a self number, because there is not a number n which added to its sum of digits gives 2188420640.

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, 433169 + ... + 438191.

It is an arithmetic number, because the mean of its divisors is an integer number (61719840).

Almost surely, 2^2188420640 is an apocalyptic number.

2188420640 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 2188420640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2962552320).

2188420640 is an abundant number, since it is smaller than the sum of its proper divisors (3736684000).

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

2188420640 is a wasteful number, since it uses less digits than its factorization.

2188420640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5434 (or 5426 counting only the distinct ones).

The product of its (nonzero) digits is 24576, while the sum is 35.

The square root of 2188420640 is about 46780.5583549406. The cubic root of 2188420640 is about 1298.3056110739.

It can be divided in two parts, 21884 and 20640, that added together give a palindrome (42524).

The spelling of 2188420640 in words is "two billion, one hundred eighty-eight million, four hundred twenty thousand, six hundred forty".