921919 has 2 divisors, whose sum is σ = 921920. Its totient is φ = 921918.

The previous prime is 921913. The next prime is 921931. The reversal of 921919 is 919129.

It is a weak prime.

It is an emirp because it is prime and its reverse (919129) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 921919 - 2³ = 921911 is a prime.

It is a super-2 number, since 2×921919² = 1699869285122, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (921911) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 460959 + 460960.

It is an arithmetic number, because the mean of its divisors is an integer number (460960).

2⁹²¹⁹¹⁹ is an apocalyptic number.

921919 is a deficient number, since it is larger than the sum of its proper divisors (1).

921919 is an equidigital number, since it uses as much as digits as its factorization.

921919 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1458, while the sum is 31.

The square root of 921919 is about 960.1661314585. The cubic root of 921919 is about 97.3264587730.

The spelling of 921919 in words is "nine hundred twenty-one thousand, nine hundred nineteen".