21418849489 has 2 divisors, whose sum is σ = 21418849490. Its totient is φ = 21418849488.

The previous prime is 21418849469. The next prime is 21418849513. The reversal of 21418849489 is 98494881412.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21379411089 + 39438400 = 146217^2 + 6280^2 .

It is a cyclic number.

It is not a de Polignac number, because 21418849489 - 2²³ = 21410460881 is a prime.

It is a super-2 number, since 2×21418849489² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21418849469) 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, 10709424744 + 10709424745.

It is an arithmetic number, because the mean of its divisors is an integer number (10709424745).

Almost surely, 2^21418849489 is an apocalyptic number.

It is an amenable number.

21418849489 is a deficient number, since it is larger than the sum of its proper divisors (1).

21418849489 is an equidigital number, since it uses as much as digits as its factorization.

21418849489 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5308416, while the sum is 58.

The spelling of 21418849489 in words is "twenty-one billion, four hundred eighteen million, eight hundred forty-nine thousand, four hundred eighty-nine".