2185503809 has 2 divisors, whose sum is σ = 2185503810. Its totient is φ = 2185503808.

The previous prime is 2185503797. The next prime is 2185503851. The reversal of 2185503809 is 9083055812.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2029953025 + 155550784 = 45055^2 + 12472^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2185503809 is a prime.

It is not a weakly prime, because it can be changed into another prime (2185503889) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1092751904 + 1092751905.

It is an arithmetic number, because the mean of its divisors is an integer number (1092751905).

Almost surely, 2^2185503809 is an apocalyptic number.

It is an amenable number.

2185503809 is a deficient number, since it is larger than the sum of its proper divisors (1).

2185503809 is an equidigital number, since it uses as much as digits as its factorization.

2185503809 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 86400, while the sum is 41.

The square root of 2185503809 is about 46749.3722845559. The cubic root of 2185503809 is about 1297.7285401486.

The spelling of 2185503809 in words is "two billion, one hundred eighty-five million, five hundred three thousand, eight hundred nine".