2188645986 has 32 divisors (see below), whose sum is σ = 4676463360. Its totient is φ = 680833296.

The previous prime is 2188645981. The next prime is 2188645997. The reversal of 2188645986 is 6895468812.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (57).

It is not an unprimeable number, because it can be changed into a prime (2188645981) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 135636 + ... + 150911.

It is an arithmetic number, because the mean of its divisors is an integer number (146139480).

Almost surely, 2^2188645986 is an apocalyptic number.

2188645986 is an abundant number, since it is smaller than the sum of its proper divisors (2487817374).

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

2188645986 is a wasteful number, since it uses less digits than its factorization.

2188645986 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 286638.

The product of its digits is 6635520, while the sum is 57.

The square root of 2188645986 is about 46782.9668362322. The cubic root of 2188645986 is about 1298.3501725763.

The spelling of 2188645986 in words is "two billion, one hundred eighty-eight million, six hundred forty-five thousand, nine hundred eighty-six".