1225443421 has 2 divisors, whose sum is σ = 1225443422. Its totient is φ = 1225443420.

The previous prime is 1225443409. The next prime is 1225443431. The reversal of 1225443421 is 1243445221.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 961868196 + 263575225 = 31014^2 + 16235^2 .

It is an emirp because it is prime and its reverse (1243445221) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1225443421 - 2¹⁹ = 1224919133 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1225443421.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1225443431) 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, 612721710 + 612721711.

It is an arithmetic number, because the mean of its divisors is an integer number (612721711).

Almost surely, 2^1225443421 is an apocalyptic number.

It is an amenable number.

1225443421 is a deficient number, since it is larger than the sum of its proper divisors (1).

1225443421 is an equidigital number, since it uses as much as digits as its factorization.

1225443421 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 7680, while the sum is 28.

The square root of 1225443421 is about 35006.3340125755. The cubic root of 1225443421 is about 1070.1165683700.

Adding to 1225443421 its reverse (1243445221), we get a palindrome (2468888642).

The spelling of 1225443421 in words is "one billion, two hundred twenty-five million, four hundred forty-three thousand, four hundred twenty-one".