1604850991 has 2 divisors, whose sum is σ = 1604850992. Its totient is φ = 1604850990.

The previous prime is 1604850977. The next prime is 1604851043. The reversal of 1604850991 is 1990584061.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1604850991 - 2⁵ = 1604850959 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1604851991) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 802425495 + 802425496.

It is an arithmetic number, because the mean of its divisors is an integer number (802425496).

Almost surely, 2^1604850991 is an apocalyptic number.

1604850991 is a deficient number, since it is larger than the sum of its proper divisors (1).

1604850991 is an equidigital number, since it uses as much as digits as its factorization.

1604850991 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 77760, while the sum is 43.

The square root of 1604850991 is about 40060.5914958828. The cubic root of 1604850991 is about 1170.7879346820.

The spelling of 1604850991 in words is "one billion, six hundred four million, eight hundred fifty thousand, nine hundred ninety-one".