991342427 has 2 divisors, whose sum is σ = 991342428. Its totient is φ = 991342426.

The previous prime is 991342421. The next prime is 991342433. The reversal of 991342427 is 724243199.

It is a balanced prime because it is at equal distance from previous prime (991342421) and next prime (991342433).

It is an emirp because it is prime and its reverse (724243199) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 991342427 - 2⁴ = 991342411 is a prime.

It is not a weakly prime, because it can be changed into another prime (991342421) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 495671213 + 495671214.

It is an arithmetic number, because the mean of its divisors is an integer number (495671214).

Almost surely, 2^991342427 is an apocalyptic number.

991342427 is a deficient number, since it is larger than the sum of its proper divisors (1).

991342427 is an equidigital number, since it uses as much as digits as its factorization.

991342427 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 108864, while the sum is 41.

The square root of 991342427 is about 31485.5907837220. The cubic root of 991342427 is about 997.1057738696.

The spelling of 991342427 in words is "nine hundred ninety-one million, three hundred forty-two thousand, four hundred twenty-seven".