2911721 has 2 divisors, whose sum is σ = 2911722. Its totient is φ = 2911720.

The previous prime is 2911679. The next prime is 2911757. The reversal of 2911721 is 1271192.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2676496 + 235225 = 1636^2 + 485^2 .

It is a cyclic number.

It is not a de Polignac number, because 2911721 - 2¹⁰ = 2910697 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2911771) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1455860 + 1455861.

It is an arithmetic number, because the mean of its divisors is an integer number (1455861).

2^2911721 is an apocalyptic number.

It is an amenable number.

2911721 is a deficient number, since it is larger than the sum of its proper divisors (1).

2911721 is an equidigital number, since it uses as much as digits as its factorization.

2911721 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 252, while the sum is 23.

The square root of 2911721 is about 1706.3765703971. The cubic root of 2911721 is about 142.7961788922.

The spelling of 2911721 in words is "two million, nine hundred eleven thousand, seven hundred twenty-one".