21223558393 has 2 divisors, whose sum is σ = 21223558394. Its totient is φ = 21223558392.

The previous prime is 21223558351. The next prime is 21223558423. The reversal of 21223558393 is 39385532212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21223536489 + 21904 = 145683^2 + 148^2 .

It is a cyclic number.

It is not a de Polignac number, because 21223558393 - 2²¹ = 21221461241 is a prime.

It is a super-2 number, since 2×21223558393² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21223558793) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10611779196 + 10611779197.

It is an arithmetic number, because the mean of its divisors is an integer number (10611779197).

Almost surely, 2^21223558393 is an apocalyptic number.

It is an amenable number.

21223558393 is a deficient number, since it is larger than the sum of its proper divisors (1).

21223558393 is an equidigital number, since it uses as much as digits as its factorization.

21223558393 is an evil number, because the sum of its binary digits is even.

The product of its digits is 388800, while the sum is 43.

The spelling of 21223558393 in words is "twenty-one billion, two hundred twenty-three million, five hundred fifty-eight thousand, three hundred ninety-three".