1648641 has 4 divisors (see below), whose sum is σ = 2198192. Its totient is φ = 1099092.

The previous prime is 1648613. The next prime is 1648697. The reversal of 1648641 is 1468461.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1468461 = 3 ⋅489487.

It is not a de Polignac number, because 1648641 - 2⁷ = 1648513 is a prime.

It is a D-number.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1648599 and 1648608.

It is not an unprimeable number, because it can be changed into a prime (1648601) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 274771 + ... + 274776.

It is an arithmetic number, because the mean of its divisors is an integer number (549548).

It is a Proth number, since it is equal to 805 ⋅ 2¹¹ + 1 and 805 < 2¹¹.

2^1648641 is an apocalyptic number.

It is an amenable number.

1648641 is a deficient number, since it is larger than the sum of its proper divisors (549551).

1648641 is an equidigital number, since it uses as much as digits as its factorization.

1648641 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 549550.

The product of its digits is 4608, while the sum is 30.

The square root of 1648641 is about 1283.9941588652. The cubic root of 1648641 is about 118.1341240398.

The spelling of 1648641 in words is "one million, six hundred forty-eight thousand, six hundred forty-one".