1645606 has 4 divisors (see below), whose sum is σ = 2468412. Its totient is φ = 822802.

The previous prime is 1645603. The next prime is 1645607. The reversal of 1645606 is 6065461.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1645601) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 411400 + ... + 411403.

It is an arithmetic number, because the mean of its divisors is an integer number (617103).

2^1645606 is an apocalyptic number.

1645606 is a deficient number, since it is larger than the sum of its proper divisors (822806).

1645606 is an equidigital number, since it uses as much as digits as its factorization.

1645606 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 822805.

The product of its (nonzero) digits is 4320, while the sum is 28.

The square root of 1645606 is about 1282.8117554809. The cubic root of 1645606 is about 118.0615880736.

The spelling of 1645606 in words is "one million, six hundred forty-five thousand, six hundred six".