21305454393 has 8 divisors (see below), whose sum is σ = 28688533056. Its totient is φ = 14063006000.

The previous prime is 21305454377. The next prime is 21305454403. The reversal of 21305454393 is 39345450312.

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 21305454393 - 2⁴ = 21305454377 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21305454193) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 35157213 + ... + 35157818.

It is an arithmetic number, because the mean of its divisors is an integer number (3586066632).

Almost surely, 2^21305454393 is an apocalyptic number.

It is an amenable number.

21305454393 is a deficient number, since it is larger than the sum of its proper divisors (7383078663).

21305454393 is a wasteful number, since it uses less digits than its factorization.

21305454393 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 70315135.

The product of its (nonzero) digits is 194400, while the sum is 39.

The spelling of 21305454393 in words is "twenty-one billion, three hundred five million, four hundred fifty-four thousand, three hundred ninety-three".