1223205140 has 24 divisors (see below), whose sum is σ = 2579399592. Its totient is φ = 487249920.

The previous prime is 1223205119. The next prime is 1223205149. The reversal of 1223205140 is 415023221.

It can be written as a sum of positive squares in 4 ways, for example, as 314423824 + 908781316 = 17732^2 + 30146^2 .

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1223205149) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 122069 + ... + 131708.

It is an arithmetic number, because the mean of its divisors is an integer number (107474983).

Almost surely, 2^1223205140 is an apocalyptic number.

1223205140 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1223205140 is an abundant number, since it is smaller than the sum of its proper divisors (1356194452).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1223205140 is a wasteful number, since it uses less digits than its factorization.

1223205140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 254027 (or 254025 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 20.

The square root of 1223205140 is about 34974.3497437765. The cubic root of 1223205140 is about 1069.4646461570.

Adding to 1223205140 its reverse (415023221), we get a palindrome (1638228361).

The spelling of 1223205140 in words is "one billion, two hundred twenty-three million, two hundred five thousand, one hundred forty".