21348009221 has 16 divisors (see below), whose sum is σ = 27533485440. Its totient is φ = 16061196480.

The previous prime is 21348009173. The next prime is 21348009223. The reversal of 21348009221 is 12290084312.

It is not a de Polignac number, because 21348009221 - 2²⁶ = 21280900357 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21348009223) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4777886 + ... + 4782351.

It is an arithmetic number, because the mean of its divisors is an integer number (1720842840).

Almost surely, 2^21348009221 is an apocalyptic number.

It is an amenable number.

21348009221 is a deficient number, since it is larger than the sum of its proper divisors (6185476219).

21348009221 is a wasteful number, since it uses less digits than its factorization.

21348009221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9560284.

The product of its (nonzero) digits is 6912, while the sum is 32.

The spelling of 21348009221 in words is "twenty-one billion, three hundred forty-eight million, nine thousand, two hundred twenty-one".