2191256380 has 48 divisors (see below), whose sum is σ = 4713194304. Its totient is φ = 855429120.

The previous prime is 2191256371. The next prime is 2191256383. The reversal of 2191256380 is 836521912.

It is a super-3 number, since 3×2191256380³ (a number of 29 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2191256383) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 199225 + ... + 209935.

It is an arithmetic number, because the mean of its divisors is an integer number (98191548).

Almost surely, 2^2191256380 is an apocalyptic number.

2191256380 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2191256380 is an abundant number, since it is smaller than the sum of its proper divisors (2521937924).

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

2191256380 is a wasteful number, since it uses less digits than its factorization.

2191256380 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10966 (or 10964 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 37.

The square root of 2191256380 is about 46810.8575012251. The cubic root of 2191256380 is about 1298.8661474425.

The spelling of 2191256380 in words is "two billion, one hundred ninety-one million, two hundred fifty-six thousand, three hundred eighty".