2191136256 has 240 divisors, whose sum is σ = 6796533744. Its totient is φ = 677117952.

The previous prime is 2191136231. The next prime is 2191136279. The reversal of 2191136256 is 6526311912.

2191136256 is a `hidden beast` number, since 2 + 19 + 1 + 13 + 625 + 6 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 2191136256.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 6501720 + ... + 6502056.

Almost surely, 2^2191136256 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 2191136256, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3398266872).

2191136256 is an abundant number, since it is smaller than the sum of its proper divisors (4605397488).

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

2191136256 is a wasteful number, since it uses less digits than its factorization.

2191136256 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 461 (or 442 counting only the distinct ones).

The product of its digits is 19440, while the sum is 36.

The square root of 2191136256 is about 46809.5744052432. The cubic root of 2191136256 is about 1298.8424125280.

The spelling of 2191136256 in words is "two billion, one hundred ninety-one million, one hundred thirty-six thousand, two hundred fifty-six".