21273967009 has 4 divisors (see below), whose sum is σ = 21275649216. Its totient is φ = 21272284804.

The previous prime is 21273966983. The next prime is 21273967021. The reversal of 21273967009 is 90076937212.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21273967009 - 2¹¹ = 21273964961 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21273967009.

It is not an unprimeable number, because it can be changed into a prime (21273967109) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 821989 + ... + 847474.

It is an arithmetic number, because the mean of its divisors is an integer number (5318912304).

Almost surely, 2^21273967009 is an apocalyptic number.

It is an amenable number.

21273967009 is a deficient number, since it is larger than the sum of its proper divisors (1682207).

21273967009 is a wasteful number, since it uses less digits than its factorization.

21273967009 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1682206.

The product of its (nonzero) digits is 285768, while the sum is 46.

The spelling of 21273967009 in words is "twenty-one billion, two hundred seventy-three million, nine hundred sixty-seven thousand, nine".