21745452205 has 8 divisors (see below), whose sum is σ = 26260750872. Its totient is φ = 17285556288.

The previous prime is 21745452181. The next prime is 21745452217. The reversal of 21745452205 is 50225454712.

It can be written as a sum of positive squares in 4 ways, for example, as 367795684 + 21377656521 = 19178^2 + 146211^2 .

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 21745452205 - 2⁵ = 21745452173 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 7 ways as a sum of consecutive naturals, for example, 13849822 + ... + 13851391.

It is an arithmetic number, because the mean of its divisors is an integer number (3282593859).

Almost surely, 2^21745452205 is an apocalyptic number.

It is an amenable number.

21745452205 is a deficient number, since it is larger than the sum of its proper divisors (4515298667).

21745452205 is a wasteful number, since it uses less digits than its factorization.

21745452205 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27701375.

The product of its (nonzero) digits is 112000, while the sum is 37.

The spelling of 21745452205 in words is "twenty-one billion, seven hundred forty-five million, four hundred fifty-two thousand, two hundred five".