1243220266 has 4 divisors (see below), whose sum is σ = 1864830402. Its totient is φ = 621610132.

The previous prime is 1243220243. The next prime is 1243220269. The reversal of 1243220266 is 6620223421.

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

It can be written as a sum of positive squares in only one way, i.e., 939729025 + 303491241 = 30655^2 + 17421^2 .

It is a super-2 number, since 2×1243220266² = 3091193259586221512, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1243220269) 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 as a sum of consecutive naturals, namely, 310805065 + ... + 310805068.

Almost surely, 2^1243220266 is an apocalyptic number.

1243220266 is a deficient number, since it is larger than the sum of its proper divisors (621610136).

1243220266 is an equidigital number, since it uses as much as digits as its factorization.

1243220266 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 621610135.

The product of its (nonzero) digits is 6912, while the sum is 28.

The square root of 1243220266 is about 35259.3287797712. The cubic root of 1243220266 is about 1075.2662808180.

Adding to 1243220266 its reverse (6620223421), we get a palindrome (7863443687).

The spelling of 1243220266 in words is "one billion, two hundred forty-three million, two hundred twenty thousand, two hundred sixty-six".