1648561 has 4 divisors (see below), whose sum is σ = 1651312. Its totient is φ = 1645812.

The previous prime is 1648553. The next prime is 1648567. The reversal of 1648561 is 1658461.

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.

It is a cyclic number.

It is not a de Polignac number, because 1648561 - 2³ = 1648553 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1648567) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 51 + ... + 1816.

It is an arithmetic number, because the mean of its divisors is an integer number (412828).

2^1648561 is an apocalyptic number.

It is an amenable number.

1648561 is a deficient number, since it is larger than the sum of its proper divisors (2751).

1648561 is an equidigital number, since it uses as much as digits as its factorization.

1648561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2750.

The product of its digits is 5760, while the sum is 31.

The square root of 1648561 is about 1283.9630056976. The cubic root of 1648561 is about 118.1322131967.

It can be divided in two parts, 1648 and 561, that added together give a square (2209 = 47²).

The spelling of 1648561 in words is "one million, six hundred forty-eight thousand, five hundred sixty-one".