210068541721 has 4 divisors (see below), whose sum is σ = 210115848244. Its totient is φ = 210021235200.

The previous prime is 210068541719. The next prime is 210068541827. The reversal of 210068541721 is 127145860012.

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 88797444121 + 121271097600 = 297989^2 + 348240^2 .

It is a cyclic number.

It is not a de Polignac number, because 210068541721 - 2¹ = 210068541719 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (210068641721) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 23646600 + ... + 23655481.

It is an arithmetic number, because the mean of its divisors is an integer number (52528962061).

Almost surely, 2^210068541721 is an apocalyptic number.

It is an amenable number.

210068541721 is a deficient number, since it is larger than the sum of its proper divisors (47306523).

210068541721 is an equidigital number, since it uses as much as digits as its factorization.

210068541721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 47306522.

The product of its (nonzero) digits is 26880, while the sum is 37.

The spelling of 210068541721 in words is "two hundred ten billion, sixty-eight million, five hundred forty-one thousand, seven hundred twenty-one".