1904905997 has 2 divisors, whose sum is σ = 1904905998. Its totient is φ = 1904905996.

The previous prime is 1904905973. The next prime is 1904906057. The reversal of 1904905997 is 7995094091.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1585712041 + 319193956 = 39821^2 + 17866^2 .

It is a cyclic number.

It is not a de Polignac number, because 1904905997 - 2⁸ = 1904905741 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1904905967) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 952452998 + 952452999.

It is an arithmetic number, because the mean of its divisors is an integer number (952452999).

Almost surely, 2^1904905997 is an apocalyptic number.

It is an amenable number.

1904905997 is a deficient number, since it is larger than the sum of its proper divisors (1).

1904905997 is an equidigital number, since it uses as much as digits as its factorization.

1904905997 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 918540, while the sum is 53.

The square root of 1904905997 is about 43645.2287999502. The cubic root of 1904905997 is about 1239.6274455271.

The spelling of 1904905997 in words is "one billion, nine hundred four million, nine hundred five thousand, nine hundred ninety-seven".