1223321661 has 6 divisors (see below), whose sum is σ = 1767020190. Its totient is φ = 815547768.

The previous prime is 1223321651. The next prime is 1223321681. The reversal of 1223321661 is 1661233221.

It can be written as a sum of positive squares in only one way, i.e., 901800900 + 321520761 = 30030^2 + 17931^2 .

It is not a de Polignac number, because 1223321661 - 2⁹ = 1223321149 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1223321651) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 67962306 + ... + 67962323.

It is an arithmetic number, because the mean of its divisors is an integer number (294503365).

Almost surely, 2^1223321661 is an apocalyptic number.

It is an amenable number.

1223321661 is a deficient number, since it is larger than the sum of its proper divisors (543698529).

1223321661 is a wasteful number, since it uses less digits than its factorization.

1223321661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 135924635 (or 135924632 counting only the distinct ones).

The product of its digits is 2592, while the sum is 27.

The square root of 1223321661 is about 34976.0155106324. The cubic root of 1223321661 is about 1069.4986037027.

Adding to 1223321661 its reverse (1661233221), we get a palindrome (2884554882).

The spelling of 1223321661 in words is "one billion, two hundred twenty-three million, three hundred twenty-one thousand, six hundred sixty-one".