21422434457 has 2 divisors, whose sum is σ = 21422434458. Its totient is φ = 21422434456.

The previous prime is 21422434421. The next prime is 21422434487. The reversal of 21422434457 is 75443422412.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18286882441 + 3135552016 = 135229^2 + 55996^2 .

It is a cyclic number.

It is not a de Polignac number, because 21422434457 - 2¹⁰ = 21422433433 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21422434457.

It is not a weakly prime, because it can be changed into another prime (21422434487) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10711217228 + 10711217229.

It is an arithmetic number, because the mean of its divisors is an integer number (10711217229).

Almost surely, 2^21422434457 is an apocalyptic number.

It is an amenable number.

21422434457 is a deficient number, since it is larger than the sum of its proper divisors (1).

21422434457 is an equidigital number, since it uses as much as digits as its factorization.

21422434457 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 215040, while the sum is 38.

Adding to 21422434457 its reverse (75443422412), we get a palindrome (96865856869).

The spelling of 21422434457 in words is "twenty-one billion, four hundred twenty-two million, four hundred thirty-four thousand, four hundred fifty-seven".