928208921 has 2 divisors, whose sum is σ = 928208922. Its totient is φ = 928208920.

The previous prime is 928208903. The next prime is 928208923. The reversal of 928208921 is 129802829.

928208921 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 can be written as a sum of positive squares in only one way, i.e., 927872521 + 336400 = 30461^2 + 580^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-928208921 is a prime.

Together with 928208923, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (928208923) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 464104460 + 464104461.

It is an arithmetic number, because the mean of its divisors is an integer number (464104461).

Almost surely, 2^928208921 is an apocalyptic number.

It is an amenable number.

928208921 is a deficient number, since it is larger than the sum of its proper divisors (1).

928208921 is an equidigital number, since it uses as much as digits as its factorization.

928208921 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 41472, while the sum is 41.

The square root of 928208921 is about 30466.5213143870. The cubic root of 928208921 is about 975.4729841002.

The spelling of 928208921 in words is "nine hundred twenty-eight million, two hundred eight thousand, nine hundred twenty-one".