1009644 has 12 divisors (see below), whose sum is σ = 2355864. Its totient is φ = 336544.

The previous prime is 1009643. The next prime is 1009649. The reversal of 1009644 is 4469001.

It is a tau number, because it is divible by the number of its divisors (12).

It is an Ulam number.

It is not an unprimeable number, because it can be changed into a prime (1009643) 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, 42057 + ... + 42080.

It is an arithmetic number, because the mean of its divisors is an integer number (196322).

2^1009644 is an apocalyptic number.

It is an amenable number.

1009644 is an abundant number, since it is smaller than the sum of its proper divisors (1346220).

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

1009644 is a wasteful number, since it uses less digits than its factorization.

1009644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 84144 (or 84142 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 24.

The square root of 1009644 is about 1004.8104298822. The cubic root of 1009644 is about 100.3204387599.

It can be divided in two parts, 1009 and 644, that added together give a triangular number (1653 = T₅₇).

The spelling of 1009644 in words is "one million, nine thousand, six hundred forty-four".