2111550006721 has 4 divisors (see below), whose sum is σ = 2111552938944. Its totient is φ = 2111547074500.

The previous prime is 2111550006707. The next prime is 2111550006803. The reversal of 2111550006721 is 1276000551112.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2111550006721 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2111550001721) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 440916 + ... + 2101786.

It is an arithmetic number, because the mean of its divisors is an integer number (527888234736).

Almost surely, 2^{2111550006721} is an apocalyptic number.

It is an amenable number.

2111550006721 is a deficient number, since it is larger than the sum of its proper divisors (2932223).

2111550006721 is a wasteful number, since it uses less digits than its factorization.

2111550006721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2932222.

The product of its (nonzero) digits is 4200, while the sum is 31.

Adding to 2111550006721 its reverse (1276000551112), we get a palindrome (3387550557833).

The spelling of 2111550006721 in words is "two trillion, one hundred eleven billion, five hundred fifty million, six thousand, seven hundred twenty-one".