1221326143 has 8 divisors (see below), whose sum is σ = 1234490400. Its totient is φ = 1208197728.

The previous prime is 1221326069. The next prime is 1221326153. The reversal of 1221326143 is 3416231221.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1221326143 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221326153) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 62598 + ... + 79756.

It is an arithmetic number, because the mean of its divisors is an integer number (154311300).

Almost surely, 2^1221326143 is an apocalyptic number.

1221326143 is a deficient number, since it is larger than the sum of its proper divisors (13164257).

1221326143 is a wasteful number, since it uses less digits than its factorization.

1221326143 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17921.

The product of its digits is 1728, while the sum is 25.

The square root of 1221326143 is about 34947.4769189422. The cubic root of 1221326143 is about 1068.9167547652.

Adding to 1221326143 its reverse (3416231221), we get a palindrome (4637557364).

The spelling of 1221326143 in words is "one billion, two hundred twenty-one million, three hundred twenty-six thousand, one hundred forty-three".