21305456011 has 8 divisors (see below), whose sum is σ = 24354584064. Its totient is φ = 18257700840.

The previous prime is 21305455987. The next prime is 21305456017. The reversal of 21305456011 is 11065450312.

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 21305456011 - 2⁷ = 21305455883 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21305456017) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 309745 + ... + 372226.

It is an arithmetic number, because the mean of its divisors is an integer number (3044323008).

Almost surely, 2^21305456011 is an apocalyptic number.

21305456011 is a deficient number, since it is larger than the sum of its proper divisors (3049128053).

21305456011 is an equidigital number, since it uses as much as digits as its factorization.

21305456011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 686441.

The product of its (nonzero) digits is 3600, while the sum is 28.

The spelling of 21305456011 in words is "twenty-one billion, three hundred five million, four hundred fifty-six thousand, eleven".