921911 has 2 divisors, whose sum is σ = 921912. Its totient is φ = 921910.

The previous prime is 921901. The next prime is 921913. The reversal of 921911 is 119129.

921911 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is an emirp because it is prime and its reverse (119129) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-921911 is a prime.

It is a Sophie Germain prime.

Together with 921913, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (921913) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 460955 + 460956.

It is an arithmetic number, because the mean of its divisors is an integer number (460956).

2⁹²¹⁹¹¹ is an apocalyptic number.

921911 is a deficient number, since it is larger than the sum of its proper divisors (1).

921911 is an equidigital number, since it uses as much as digits as its factorization.

921911 is an evil number, because the sum of its binary digits is even.

The product of its digits is 162, while the sum is 23.

The square root of 921911 is about 960.1619655037. The cubic root of 921911 is about 97.3261772538.

The spelling of 921911 in words is "nine hundred twenty-one thousand, nine hundred eleven".