1223205406 has 4 divisors (see below), whose sum is σ = 1834808112. Its totient is φ = 611602702.

The previous prime is 1223205359. The next prime is 1223205407. The reversal of 1223205406 is 6045023221.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1223205407) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 305801350 + ... + 305801353.

It is an arithmetic number, because the mean of its divisors is an integer number (458702028).

Almost surely, 2^1223205406 is an apocalyptic number.

1223205406 is a deficient number, since it is larger than the sum of its proper divisors (611602706).

1223205406 is an equidigital number, since it uses as much as digits as its factorization.

1223205406 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 611602705.

The product of its (nonzero) digits is 2880, while the sum is 25.

The square root of 1223205406 is about 34974.3535465632. The cubic root of 1223205406 is about 1069.4647236794.

Adding to 1223205406 its reverse (6045023221), we get a palindrome (7268228627).

It can be divided in two parts, 12 and 23205406, that multiplied together give a palindrome (278464872).

The spelling of 1223205406 in words is "one billion, two hundred twenty-three million, two hundred five thousand, four hundred six".