1221312235 has 32 divisors (see below), whose sum is σ = 1781196480. Its totient is φ = 791616000.

The previous prime is 1221312217. The next prime is 1221312269. The reversal of 1221312235 is 5322131221.

It is not a de Polignac number, because 1221312235 - 2⁵ = 1221312203 is a prime.

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 in 31 ways as a sum of consecutive naturals, for example, 8716 + ... + 50185.

It is an arithmetic number, because the mean of its divisors is an integer number (55662390).

Almost surely, 2^1221312235 is an apocalyptic number.

1221312235 is a deficient number, since it is larger than the sum of its proper divisors (559884245).

1221312235 is a wasteful number, since it uses less digits than its factorization.

1221312235 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 58959.

The product of its digits is 720, while the sum is 22.

The square root of 1221312235 is about 34947.2779340537. The cubic root of 1221312235 is about 1068.9126972766.

Adding to 1221312235 its reverse (5322131221), we get a palindrome (6543443456).

The spelling of 1221312235 in words is "one billion, two hundred twenty-one million, three hundred twelve thousand, two hundred thirty-five".