1321221975 has 12 divisors (see below), whose sum is σ = 2184420456. Its totient is φ = 704651680.

The previous prime is 1321221973. The next prime is 1321222013. The reversal of 1321221975 is 5791221231.

It is not a de Polignac number, because 1321221975 - 2¹ = 1321221973 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1321221973) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 8808072 + ... + 8808221.

It is an arithmetic number, because the mean of its divisors is an integer number (182035038).

Almost surely, 2^1321221975 is an apocalyptic number.

1321221975 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

1321221975 is a deficient number, since it is larger than the sum of its proper divisors (863198481).

1321221975 is a wasteful number, since it uses less digits than its factorization.

1321221975 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17616306 (or 17616301 counting only the distinct ones).

The product of its digits is 7560, while the sum is 33.

The square root of 1321221975 is about 36348.6172364232. The cubic root of 1321221975 is about 1097.2997059087.

The spelling of 1321221975 in words is "one billion, three hundred twenty-one million, two hundred twenty-one thousand, nine hundred seventy-five".