21234442753 has 2 divisors, whose sum is σ = 21234442754. Its totient is φ = 21234442752.

The previous prime is 21234442729. The next prime is 21234442819. The reversal of 21234442753 is 35724443212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18201517569 + 3032925184 = 134913^2 + 55072^2 .

It is a cyclic number.

It is not a de Polignac number, because 21234442753 - 2²¹ = 21232345601 is a prime.

It is not a weakly prime, because it can be changed into another prime (21234442253) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10617221376 + 10617221377.

It is an arithmetic number, because the mean of its divisors is an integer number (10617221377).

Almost surely, 2^21234442753 is an apocalyptic number.

It is an amenable number.

21234442753 is a deficient number, since it is larger than the sum of its proper divisors (1).

21234442753 is an equidigital number, since it uses as much as digits as its factorization.

21234442753 is an evil number, because the sum of its binary digits is even.

The product of its digits is 161280, while the sum is 37.

Adding to 21234442753 its reverse (35724443212), we get a palindrome (56958885965).

The spelling of 21234442753 in words is "twenty-one billion, two hundred thirty-four million, four hundred forty-two thousand, seven hundred fifty-three".