1216723133 has 8 divisors (see below), whose sum is σ = 1323114552. Its totient is φ = 1114200576.

The previous prime is 1216723129. The next prime is 1216723139. The reversal of 1216723133 is 3313276121.

It can be written as a sum of positive squares in 4 ways, for example, as 441546169 + 775176964 = 21013^2 + 27842^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1216723133 - 2² = 1216723129 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1216723096 and 1216723105.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1216723139) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 966560 + ... + 967817.

It is an arithmetic number, because the mean of its divisors is an integer number (165389319).

Almost surely, 2^1216723133 is an apocalyptic number.

It is an amenable number.

1216723133 is a deficient number, since it is larger than the sum of its proper divisors (106391419).

1216723133 is a wasteful number, since it uses less digits than its factorization.

1216723133 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1934431.

The product of its digits is 4536, while the sum is 29.

The square root of 1216723133 is about 34881.5586377673. The cubic root of 1216723133 is about 1067.5721975277.

Adding to 1216723133 its reverse (3313276121), we get a palindrome (4529999254).

The spelling of 1216723133 in words is "one billion, two hundred sixteen million, seven hundred twenty-three thousand, one hundred thirty-three".