21214442393 has 2 divisors, whose sum is σ = 21214442394. Its totient is φ = 21214442392.

The previous prime is 21214442371. The next prime is 21214442399. The reversal of 21214442393 is 39324441212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11753378569 + 9461063824 = 108413^2 + 97268^2 .

It is a cyclic number.

It is not a de Polignac number, because 21214442393 - 2⁶ = 21214442329 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (21214442399) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10607221196 + 10607221197.

It is an arithmetic number, because the mean of its divisors is an integer number (10607221197).

Almost surely, 2^21214442393 is an apocalyptic number.

It is an amenable number.

21214442393 is a deficient number, since it is larger than the sum of its proper divisors (1).

21214442393 is an equidigital number, since it uses as much as digits as its factorization.

21214442393 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 41472, while the sum is 35.

The spelling of 21214442393 in words is "twenty-one billion, two hundred fourteen million, four hundred forty-two thousand, three hundred ninety-three".