1118215391 has 2 divisors, whose sum is σ = 1118215392. Its totient is φ = 1118215390.

The previous prime is 1118215381. The next prime is 1118215411. The reversal of 1118215391 is 1935128111.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1118215391 - 2¹⁰ = 1118214367 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1118215331) 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, 559107695 + 559107696.

It is an arithmetic number, because the mean of its divisors is an integer number (559107696).

Almost surely, 2^1118215391 is an apocalyptic number.

1118215391 is a deficient number, since it is larger than the sum of its proper divisors (1).

1118215391 is an equidigital number, since it uses as much as digits as its factorization.

1118215391 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2160, while the sum is 32.

The square root of 1118215391 is about 33439.7277351356. The cubic root of 1118215391 is about 1037.9469454978.

The spelling of 1118215391 in words is "one billion, one hundred eighteen million, two hundred fifteen thousand, three hundred ninety-one".