21730851755 has 8 divisors (see below), whose sum is σ = 26133346752. Its totient is φ = 17347131648.

The previous prime is 21730851713. The next prime is 21730851761. The reversal of 21730851755 is 55715803712.

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 21730851755 - 2¹⁸ = 21730589611 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4691174 + ... + 4695803.

It is an arithmetic number, because the mean of its divisors is an integer number (3266668344).

Almost surely, 2^21730851755 is an apocalyptic number.

21730851755 is a deficient number, since it is larger than the sum of its proper divisors (4402494997).

21730851755 is an equidigital number, since it uses as much as digits as its factorization.

21730851755 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9387445.

The product of its (nonzero) digits is 294000, while the sum is 44.

The spelling of 21730851755 in words is "twenty-one billion, seven hundred thirty million, eight hundred fifty-one thousand, seven hundred fifty-five".