1221332209321 has 9 divisors (see below), whose sum is σ = 1420742385399. Its totient is φ = 1046849548584.

The previous prime is 1221332209319. The next prime is 1221332209369. The reversal of 1221332209321 is 1239022331221.

The square root of 1221332209321 is 1105139.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 517471616025 + 703860593296 = 719355^2 + 838964^2 .

It is not a de Polignac number, because 1221332209321 - 2¹ = 1221332209319 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1221332209021) 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 8 ways as a sum of consecutive naturals, for example, 7657035 + ... + 7814911.

Almost surely, 2^{1221332209321} is an apocalyptic number.

1221332209321 is the 1105139-th square number.

1221332209321 is the 552570-th centered octagonal number.

It is an amenable number.

1221332209321 is a deficient number, since it is larger than the sum of its proper divisors (199410176078).

1221332209321 is an frugal number, since it uses more digits than its factorization.

1221332209321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 315768 (or 157884 counting only the distinct ones).

The product of its (nonzero) digits is 7776, while the sum is 31.

The spelling of 1221332209321 in words is "one trillion, two hundred twenty-one billion, three hundred thirty-two million, two hundred nine thousand, three hundred twenty-one".