1605211189 has 2 divisors, whose sum is σ = 1605211190. Its totient is φ = 1605211188.

The previous prime is 1605211187. The next prime is 1605211229. The reversal of 1605211189 is 9811125061.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1173610564 + 431600625 = 34258^2 + 20775^2 .

It is a cyclic number.

It is not a de Polignac number, because 1605211189 - 2¹ = 1605211187 is a prime.

It is a super-2 number, since 2×1605211189² = 5153405922581587442, which contains 22 as substring.

Together with 1605211187, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1605211187) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 802605594 + 802605595.

It is an arithmetic number, because the mean of its divisors is an integer number (802605595).

Almost surely, 2^1605211189 is an apocalyptic number.

It is an amenable number.

1605211189 is a deficient number, since it is larger than the sum of its proper divisors (1).

1605211189 is an equidigital number, since it uses as much as digits as its factorization.

1605211189 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4320, while the sum is 34.

The square root of 1605211189 is about 40065.0869086790. The cubic root of 1605211189 is about 1170.8755199529.

The spelling of 1605211189 in words is "one billion, six hundred five million, two hundred eleven thousand, one hundred eighty-nine".