921887 has 2 divisors, whose sum is σ = 921888. Its totient is φ = 921886.

The previous prime is 921871. The next prime is 921889. The reversal of 921887 is 788129.

It is a happy number.

921887 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 (788129) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 921887 - 2⁴ = 921871 is a prime.

It is a super-3 number, since 3×921887³ = 2350467914524833309, which contains 333 as substring.

Together with 921889, 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 (921889) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 460943 + 460944.

It is an arithmetic number, because the mean of its divisors is an integer number (460944).

2⁹²¹⁸⁸⁷ is an apocalyptic number.

921887 is a deficient number, since it is larger than the sum of its proper divisors (1).

921887 is an equidigital number, since it uses as much as digits as its factorization.

921887 is an evil number, because the sum of its binary digits is even.

The product of its digits is 8064, while the sum is 35.

The square root of 921887 is about 960.1494675310. The cubic root of 921887 is about 97.3253326861.

The spelling of 921887 in words is "nine hundred twenty-one thousand, eight hundred eighty-seven".