1001646 has 32 divisors (see below), whose sum is σ = 2263200. Its totient is φ = 332424.

The previous prime is 1001639. The next prime is 1001659. The reversal of 1001646 is 6461001.

It is a hoax number, since the sum of its digits (18) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 4260 + ... + 4488.

It is an arithmetic number, because the mean of its divisors is an integer number (70725).

2^1001646 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1001646, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1131600).

1001646 is an abundant number, since it is smaller than the sum of its proper divisors (1261554).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1001646 is an frugal number, since it uses more digits than its factorization.

1001646 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 252 (or 234 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

The square root of 1001646 is about 1000.8226616139. The cubic root of 1001646 is about 100.0548365907.

Adding to 1001646 its reverse (6461001), we get a palindrome (7462647).

It can be divided in two parts, 1001 and 646, that multiplied together give a palindrome (646646).

The spelling of 1001646 in words is "one million, one thousand, six hundred forty-six".