1240443121 has 2 divisors, whose sum is σ = 1240443122. Its totient is φ = 1240443120.

The previous prime is 1240443109. The next prime is 1240443143. The reversal of 1240443121 is 1213440421.

It is a happy number.

It is an a-pointer prime, because the next prime (1240443143) can be obtained adding 1240443121 to its sum of digits (22).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 693584896 + 546858225 = 26336^2 + 23385^2 .

It is an emirp because it is prime and its reverse (1213440421) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1240443121 - 2⁷ = 1240442993 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1240443092 and 1240443101.

It is not a weakly prime, because it can be changed into another prime (1240443161) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 620221560 + 620221561.

It is an arithmetic number, because the mean of its divisors is an integer number (620221561).

Almost surely, 2^1240443121 is an apocalyptic number.

It is an amenable number.

1240443121 is a deficient number, since it is larger than the sum of its proper divisors (1).

1240443121 is an equidigital number, since it uses as much as digits as its factorization.

1240443121 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 768, while the sum is 22.

The square root of 1240443121 is about 35219.9250567062. The cubic root of 1240443121 is about 1074.4650292204.

Adding to 1240443121 its reverse (1213440421), we get a palindrome (2453883542).

The spelling of 1240443121 in words is "one billion, two hundred forty million, four hundred forty-three thousand, one hundred twenty-one".