2012011721 has 2 divisors, whose sum is σ = 2012011722. Its totient is φ = 2012011720.

The previous prime is 2012011691. The next prime is 2012011723. The reversal of 2012011721 is 1271102102.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1225770121 + 786241600 = 35011^2 + 28040^2 .

It is a cyclic number.

It is not a de Polignac number, because 2012011721 - 2¹⁰ = 2012010697 is a prime.

Together with 2012011723, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 2012011721.

It is not a weakly prime, because it can be changed into another prime (2012011723) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1006005860 + 1006005861.

It is an arithmetic number, because the mean of its divisors is an integer number (1006005861).

Almost surely, 2^2012011721 is an apocalyptic number.

It is an amenable number.

2012011721 is a deficient number, since it is larger than the sum of its proper divisors (1).

2012011721 is an equidigital number, since it uses as much as digits as its factorization.

2012011721 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 56, while the sum is 17.

The square root of 2012011721 is about 44855.4536372112. The cubic root of 2012011721 is about 1262.4383204975.

Adding to 2012011721 its reverse (1271102102), we get a palindrome (3283113823).

The spelling of 2012011721 in words is "two billion, twelve million, eleven thousand, seven hundred twenty-one".