21453516805 has 16 divisors (see below), whose sum is σ = 29424570624. Its totient is φ = 14709680640.

The previous prime is 21453516779. The next prime is 21453516827. The reversal of 21453516805 is 50861535412.

It is not a de Polignac number, because 21453516805 - 2⁷ = 21453516677 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 542040 + ... + 580270.

It is an arithmetic number, because the mean of its divisors is an integer number (1839035664).

Almost surely, 2^21453516805 is an apocalyptic number.

It is an amenable number.

21453516805 is a deficient number, since it is larger than the sum of its proper divisors (7971053819).

21453516805 is a wasteful number, since it uses less digits than its factorization.

21453516805 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 54276.

The product of its (nonzero) digits is 144000, while the sum is 40.

The spelling of 21453516805 in words is "twenty-one billion, four hundred fifty-three million, five hundred sixteen thousand, eight hundred five".