21708058045 has 4 divisors (see below), whose sum is σ = 26049669660. Its totient is φ = 17366446432.

The previous prime is 21708058003. The next prime is 21708058051. The reversal of 21708058045 is 54085080712.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 10187470489 + 11520587556 = 100933^2 + 107334^2 .

It is a cyclic number.

It is not a de Polignac number, because 21708058045 - 2¹⁵ = 21708025277 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a junction number, because it is equal to n+sod(n) for n = 21708057989 and 21708058007.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2170805800 + ... + 2170805809.

It is an arithmetic number, because the mean of its divisors is an integer number (6512417415).

Almost surely, 2^21708058045 is an apocalyptic number.

It is an amenable number.

21708058045 is a deficient number, since it is larger than the sum of its proper divisors (4341611615).

21708058045 is an equidigital number, since it uses as much as digits as its factorization.

21708058045 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4341611614.

The product of its (nonzero) digits is 89600, while the sum is 40.

The spelling of 21708058045 in words is "twenty-one billion, seven hundred eight million, fifty-eight thousand, forty-five".