921604393 has 2 divisors, whose sum is σ = 921604394. Its totient is φ = 921604392.

The previous prime is 921604381. The next prime is 921604403. The reversal of 921604393 is 393406129.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 916091289 + 5513104 = 30267^2 + 2348^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-921604393 is a prime.

It is not a weakly prime, because it can be changed into another prime (921604303) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 460802196 + 460802197.

It is an arithmetic number, because the mean of its divisors is an integer number (460802197).

Almost surely, 2^921604393 is an apocalyptic number.

It is an amenable number.

921604393 is a deficient number, since it is larger than the sum of its proper divisors (1).

921604393 is an equidigital number, since it uses as much as digits as its factorization.

921604393 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 34992, while the sum is 37.

The square root of 921604393 is about 30357.9378911019. The cubic root of 921604393 is about 973.1538655343.

The spelling of 921604393 in words is "nine hundred twenty-one million, six hundred four thousand, three hundred ninety-three".