21758480185 has 8 divisors (see below), whose sum is σ = 28118651400. Its totient is φ = 16067800704.

The previous prime is 21758480153. The next prime is 21758480203. The reversal of 21758480185 is 58108485712.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 595213609 + 21163266576 = 24397^2 + 145476^2 .

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 21758480185 - 2⁵ = 21758480153 is a prime.

It is a super-2 number, since 2×21758480185² (a number of 21 digits) contains 22 as substring.

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, 167372860 + ... + 167372989.

It is an arithmetic number, because the mean of its divisors is an integer number (3514831425).

Almost surely, 2^21758480185 is an apocalyptic number.

It is an amenable number.

21758480185 is a deficient number, since it is larger than the sum of its proper divisors (6360171215).

21758480185 is a wasteful number, since it uses less digits than its factorization.

21758480185 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 334745867.

The product of its (nonzero) digits is 716800, while the sum is 49.

The spelling of 21758480185 in words is "twenty-one billion, seven hundred fifty-eight million, four hundred eighty thousand, one hundred eighty-five".