1221123427 has 2 divisors, whose sum is σ = 1221123428. Its totient is φ = 1221123426.

The previous prime is 1221123419. The next prime is 1221123451. The reversal of 1221123427 is 7243211221.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1221123427 - 2³ = 1221123419 is a prime.

It is a super-2 number, since 2×1221123427² = 2982284847936448658, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1221123457) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610561713 + 610561714.

It is an arithmetic number, because the mean of its divisors is an integer number (610561714).

Almost surely, 2^1221123427 is an apocalyptic number.

1221123427 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221123427 is an equidigital number, since it uses as much as digits as its factorization.

1221123427 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1344, while the sum is 25.

The square root of 1221123427 is about 34944.5765033717. The cubic root of 1221123427 is about 1068.8576118083.

Adding to 1221123427 its reverse (7243211221), we get a palindrome (8464334648).

The spelling of 1221123427 in words is "one billion, two hundred twenty-one million, one hundred twenty-three thousand, four hundred twenty-seven".