21343215149 has 2 divisors, whose sum is σ = 21343215150. Its totient is φ = 21343215148.

The previous prime is 21343215121. The next prime is 21343215247. The reversal of 21343215149 is 94151234312.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21046755625 + 296459524 = 145075^2 + 17218^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21343215149 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21343265149) 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, 10671607574 + 10671607575.

It is an arithmetic number, because the mean of its divisors is an integer number (10671607575).

Almost surely, 2^21343215149 is an apocalyptic number.

It is an amenable number.

21343215149 is a deficient number, since it is larger than the sum of its proper divisors (1).

21343215149 is an equidigital number, since it uses as much as digits as its factorization.

21343215149 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 25920, while the sum is 35.

The spelling of 21343215149 in words is "twenty-one billion, three hundred forty-three million, two hundred fifteen thousand, one hundred forty-nine".