1216022311 has 4 divisors (see below), whose sum is σ = 1389739792. Its totient is φ = 1042304832.

The previous prime is 1216022261. The next prime is 1216022323. The reversal of 1216022311 is 1132206121.

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

It is a cyclic number.

It is not a de Polignac number, because 1216022311 - 2¹³ = 1216014119 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1216022341) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 86858730 + ... + 86858743.

It is an arithmetic number, because the mean of its divisors is an integer number (347434948).

Almost surely, 2^1216022311 is an apocalyptic number.

1216022311 is a deficient number, since it is larger than the sum of its proper divisors (173717481).

1216022311 is an equidigital number, since it uses as much as digits as its factorization.

1216022311 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 173717480.

The product of its (nonzero) digits is 144, while the sum is 19.

The square root of 1216022311 is about 34871.5114527604. The cubic root of 1216022311 is about 1067.3671873775.

Adding to 1216022311 its reverse (1132206121), we get a palindrome (2348228432).

The spelling of 1216022311 in words is "one billion, two hundred sixteen million, twenty-two thousand, three hundred eleven".