2117912128 has 56 divisors (see below), whose sum is σ = 4393509120. Its totient is φ = 1011056640.

The previous prime is 2117912087. The next prime is 2117912129. The reversal of 2117912128 is 8212197112.

It is a junction number, because it is equal to n+sod(n) for n = 2117912093 and 2117912102.

It is not an unprimeable number, because it can be changed into a prime (2117912129) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1131033 + ... + 1132903.

It is an arithmetic number, because the mean of its divisors is an integer number (78455520).

Almost surely, 2^2117912128 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2117912128, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2196754560).

2117912128 is an abundant number, since it is smaller than the sum of its proper divisors (2275596992).

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

2117912128 is a wasteful number, since it uses less digits than its factorization.

2117912128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2675 (or 2665 counting only the distinct ones).

The product of its digits is 4032, while the sum is 34.

The square root of 2117912128 is about 46020.7793067436. The cubic root of 2117912128 is about 1284.2097980505.

The spelling of 2117912128 in words is "two billion, one hundred seventeen million, nine hundred twelve thousand, one hundred twenty-eight".