1216312126 has 4 divisors (see below), whose sum is σ = 1824468192. Its totient is φ = 608156062.

The previous prime is 1216312099. The next prime is 1216312159. The reversal of 1216312126 is 6212136121.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a self number, because there is not a number n which added to its sum of digits gives 1216312126.

It is a congruent number.

It is an unprimeable number.

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, 304078030 + ... + 304078033.

It is an arithmetic number, because the mean of its divisors is an integer number (456117048).

Almost surely, 2^1216312126 is an apocalyptic number.

1216312126 is a deficient number, since it is larger than the sum of its proper divisors (608156066).

1216312126 is an equidigital number, since it uses as much as digits as its factorization.

1216312126 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 608156065.

The product of its digits is 864, while the sum is 25.

The square root of 1216312126 is about 34875.6666746315. Note that the first 4 decimals coincide. The cubic root of 1216312126 is about 1067.4519759670.

Adding to 1216312126 its reverse (6212136121), we get a palindrome (7428448247).

The spelling of 1216312126 in words is "one billion, two hundred sixteen million, three hundred twelve thousand, one hundred twenty-six".