2191233438 has 64 divisors (see below), whose sum is σ = 4999579200. Its totient is φ = 710968320.

The previous prime is 2191233409. The next prime is 2191233439. The reversal of 2191233438 is 8343321912.

2191233438 is a `hidden beast` number, since 2 + 191 + 2 + 33 + 438 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2191233439) 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, 1312068 + ... + 1313736.

It is an arithmetic number, because the mean of its divisors is an integer number (78118425).

Almost surely, 2^2191233438 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2191233438, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2499789600).

2191233438 is an abundant number, since it is smaller than the sum of its proper divisors (2808345762).

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

2191233438 is a wasteful number, since it uses less digits than its factorization.

2191233438 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2314 (or 2308 counting only the distinct ones).

The product of its digits is 31104, while the sum is 36.

The square root of 2191233438 is about 46810.6124505971. The cubic root of 2191233438 is about 1298.8616144736.

The spelling of 2191233438 in words is "two billion, one hundred ninety-one million, two hundred thirty-three thousand, four hundred thirty-eight".