21342602721 has 8 divisors (see below), whose sum is σ = 31043785824. Its totient is φ = 12934910720.

The previous prime is 21342602707. The next prime is 21342602731. The reversal of 21342602721 is 12720624312.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21342602721 - 2⁶ = 21342602657 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21342602731) 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 7 ways as a sum of consecutive naturals, for example, 323372736 + ... + 323372801.

It is an arithmetic number, because the mean of its divisors is an integer number (3880473228).

Almost surely, 2^21342602721 is an apocalyptic number.

It is an amenable number.

21342602721 is a deficient number, since it is larger than the sum of its proper divisors (9701183103).

21342602721 is a wasteful number, since it uses less digits than its factorization.

21342602721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 646745551.

The product of its (nonzero) digits is 8064, while the sum is 30.

The spelling of 21342602721 in words is "twenty-one billion, three hundred forty-two million, six hundred two thousand, seven hundred twenty-one".