2178132791 has 2 divisors, whose sum is σ = 2178132792. Its totient is φ = 2178132790.

The previous prime is 2178132739. The next prime is 2178132829. The reversal of 2178132791 is 1972318712.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2178132791 is a prime.

It is a super-4 number, since 4×2178132791⁴ (a number of 38 digits) contains 4444 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2178132091) 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 as a sum of consecutive naturals, namely, 1089066395 + 1089066396.

It is an arithmetic number, because the mean of its divisors is an integer number (1089066396).

Almost surely, 2^2178132791 is an apocalyptic number.

2178132791 is a deficient number, since it is larger than the sum of its proper divisors (1).

2178132791 is an equidigital number, since it uses as much as digits as its factorization.

2178132791 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 42336, while the sum is 41.

The square root of 2178132791 is about 46670.4702247578. The cubic root of 2178132791 is about 1296.2679532755.

The spelling of 2178132791 in words is "two billion, one hundred seventy-eight million, one hundred thirty-two thousand, seven hundred ninety-one".