1645849 has 2 divisors, whose sum is σ = 1645850. Its totient is φ = 1645848.

The previous prime is 1645843. The next prime is 1645867. The reversal of 1645849 is 9485461.

It is a happy number.

1645849 is nontrivially palindromic in base 4.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1607824 + 38025 = 1268^2 + 195^2 .

It is an emirp because it is prime and its reverse (9485461) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1645849 - 2⁹ = 1645337 is a prime.

It is not a weakly prime, because it can be changed into another prime (1645843) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 822924 + 822925.

It is an arithmetic number, because the mean of its divisors is an integer number (822925).

2^1645849 is an apocalyptic number.

It is an amenable number.

1645849 is a deficient number, since it is larger than the sum of its proper divisors (1).

1645849 is an equidigital number, since it uses as much as digits as its factorization.

1645849 is an evil number, because the sum of its binary digits is even.

The product of its digits is 34560, while the sum is 37.

The square root of 1645849 is about 1282.9064658033. The cubic root of 1645849 is about 118.0673990138.

The spelling of 1645849 in words is "one million, six hundred forty-five thousand, eight hundred forty-nine".