21413444249 has 2 divisors, whose sum is σ = 21413444250. Its totient is φ = 21413444248.

The previous prime is 21413444203. The next prime is 21413444257. The reversal of 21413444249 is 94244431412.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18880134025 + 2533310224 = 137405^2 + 50332^2 .

It is a cyclic number.

It is not a de Polignac number, because 21413444249 - 2⁸ = 21413443993 is a prime.

It is not a weakly prime, because it can be changed into another prime (21413444449) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10706722124 + 10706722125.

It is an arithmetic number, because the mean of its divisors is an integer number (10706722125).

Almost surely, 2^21413444249 is an apocalyptic number.

It is an amenable number.

21413444249 is a deficient number, since it is larger than the sum of its proper divisors (1).

21413444249 is an equidigital number, since it uses as much as digits as its factorization.

21413444249 is an evil number, because the sum of its binary digits is even.

The product of its digits is 110592, while the sum is 38.

The spelling of 21413444249 in words is "twenty-one billion, four hundred thirteen million, four hundred forty-four thousand, two hundred forty-nine".