21144216479 has 2 divisors, whose sum is σ = 21144216480. Its totient is φ = 21144216478.

The previous prime is 21144216449. The next prime is 21144216487. The reversal of 21144216479 is 97461244112.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21144216479 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21144216449) 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, 10572108239 + 10572108240.

It is an arithmetic number, because the mean of its divisors is an integer number (10572108240).

Almost surely, 2^21144216479 is an apocalyptic number.

21144216479 is a deficient number, since it is larger than the sum of its proper divisors (1).

21144216479 is an equidigital number, since it uses as much as digits as its factorization.

21144216479 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 96768, while the sum is 41.

The spelling of 21144216479 in words is "twenty-one billion, one hundred forty-four million, two hundred sixteen thousand, four hundred seventy-nine".