921945839 has 2 divisors, whose sum is σ = 921945840. Its totient is φ = 921945838.

The previous prime is 921945833. The next prime is 921945847. The reversal of 921945839 is 938549129.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 921945839 - 2¹² = 921941743 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 (921945833) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 460972919 + 460972920.

It is an arithmetic number, because the mean of its divisors is an integer number (460972920).

Almost surely, 2^921945839 is an apocalyptic number.

921945839 is a deficient number, since it is larger than the sum of its proper divisors (1).

921945839 is an equidigital number, since it uses as much as digits as its factorization.

921945839 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 699840, while the sum is 50.

The square root of 921945839 is about 30363.5610395092. The cubic root of 921945839 is about 973.2740322313.

The spelling of 921945839 in words is "nine hundred twenty-one million, nine hundred forty-five thousand, eight hundred thirty-nine".