21235427593 has 2 divisors, whose sum is σ = 21235427594. Its totient is φ = 21235427592.

The previous prime is 21235427581. The next prime is 21235427663. The reversal of 21235427593 is 39572453212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17867134224 + 3368293369 = 133668^2 + 58037^2 .

It is a cyclic number.

It is not a de Polignac number, because 21235427593 - 2²¹ = 21233330441 is a prime.

It is not a weakly prime, because it can be changed into another prime (21235437593) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10617713796 + 10617713797.

It is an arithmetic number, because the mean of its divisors is an integer number (10617713797).

Almost surely, 2^21235427593 is an apocalyptic number.

It is an amenable number.

21235427593 is a deficient number, since it is larger than the sum of its proper divisors (1).

21235427593 is an equidigital number, since it uses as much as digits as its factorization.

21235427593 is an evil number, because the sum of its binary digits is even.

The product of its digits is 453600, while the sum is 43.

The spelling of 21235427593 in words is "twenty-one billion, two hundred thirty-five million, four hundred twenty-seven thousand, five hundred ninety-three".