1648591 has 4 divisors (see below), whose sum is σ = 1884112. Its totient is φ = 1413072.

The previous prime is 1648589. The next prime is 1648601. The reversal of 1648591 is 1958461.

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

It is a cyclic number.

It is not a de Polignac number, because 1648591 - 2¹ = 1648589 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1648531) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 117750 + ... + 117763.

It is an arithmetic number, because the mean of its divisors is an integer number (471028).

2^1648591 is an apocalyptic number.

1648591 is a deficient number, since it is larger than the sum of its proper divisors (235521).

1648591 is an equidigital number, since it uses as much as digits as its factorization.

1648591 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 235520.

The product of its digits is 8640, while the sum is 34.

The square root of 1648591 is about 1283.9746882240. The cubic root of 1648591 is about 118.1329297701.

The spelling of 1648591 in words is "one million, six hundred forty-eight thousand, five hundred ninety-one".