1221233311 has 2 divisors, whose sum is σ = 1221233312. Its totient is φ = 1221233310.

The previous prime is 1221233309. The next prime is 1221233329. The reversal of 1221233311 is 1133321221.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1221233311 - 2¹ = 1221233309 is a prime.

Together with 1221233309, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1221213311) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610616655 + 610616656.

It is an arithmetic number, because the mean of its divisors is an integer number (610616656).

Almost surely, 2^1221233311 is an apocalyptic number.

1221233311 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221233311 is an equidigital number, since it uses as much as digits as its factorization.

1221233311 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 216, while the sum is 19.

The square root of 1221233311 is about 34946.1487291518. The cubic root of 1221233311 is about 1068.8896715833.

Adding to 1221233311 its reverse (1133321221), we get a palindrome (2354554532).

The spelling of 1221233311 in words is "one billion, two hundred twenty-one million, two hundred thirty-three thousand, three hundred eleven".