1604872691 has 2 divisors, whose sum is σ = 1604872692. Its totient is φ = 1604872690.

The previous prime is 1604872649. The next prime is 1604872723. The reversal of 1604872691 is 1962784061.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1604872691 - 2⁶ = 1604872627 is a prime.

It is not a weakly prime, because it can be changed into another prime (1604872631) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 802436345 + 802436346.

It is an arithmetic number, because the mean of its divisors is an integer number (802436346).

Almost surely, 2^1604872691 is an apocalyptic number.

1604872691 is a deficient number, since it is larger than the sum of its proper divisors (1).

1604872691 is an equidigital number, since it uses as much as digits as its factorization.

1604872691 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 145152, while the sum is 44.

The square root of 1604872691 is about 40060.8623347027. The cubic root of 1604872691 is about 1170.7932115964.

The spelling of 1604872691 in words is "one billion, six hundred four million, eight hundred seventy-two thousand, six hundred ninety-one".