1221122321 has 2 divisors, whose sum is σ = 1221122322. Its totient is φ = 1221122320.

The previous prime is 1221122317. The next prime is 1221122327. The reversal of 1221122321 is 1232211221.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1019908096 + 201214225 = 31936^2 + 14185^2 .

It is a cyclic number.

It is not a de Polignac number, because 1221122321 - 2² = 1221122317 is a prime.

It is a super-2 number, since 2×1221122321² = 2982279445688854082, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1221122321.

It is not a weakly prime, because it can be changed into another prime (1221122327) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610561160 + 610561161.

It is an arithmetic number, because the mean of its divisors is an integer number (610561161).

Almost surely, 2^1221122321 is an apocalyptic number.

It is an amenable number.

1221122321 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221122321 is an equidigital number, since it uses as much as digits as its factorization.

1221122321 is an evil number, because the sum of its binary digits is even.

The product of its digits is 96, while the sum is 17.

The square root of 1221122321 is about 34944.5606783087. The cubic root of 1221122321 is about 1068.8572891117.

Adding to 1221122321 its reverse (1232211221), we get a palindrome (2453333542).

Subtracting 1221122321 from its reverse (1232211221), we obtain a square (11088900 = 3330²).

It can be divided in two parts, 1221 and 122321, that multiplied together give a palindrome (149353941).

The spelling of 1221122321 in words is "one billion, two hundred twenty-one million, one hundred twenty-two thousand, three hundred twenty-one".