642944 has 16 divisors (see below), whose sum is σ = 1281120. Its totient is φ = 321408.

The previous prime is 642937. The next prime is 642947. The reversal of 642944 is 449246.

It is a tau number, because it is divible by the number of its divisors (16).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642947) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2384 + ... + 2639.

It is an arithmetic number, because the mean of its divisors is an integer number (80070).

2⁶⁴²⁹⁴⁴ is an apocalyptic number.

642944 is a gapful number since it is divisible by the number (64) formed by its first and last digit.

It is an amenable number.

642944 is a deficient number, since it is larger than the sum of its proper divisors (638176).

642944 is an equidigital number, since it uses as much as digits as its factorization.

642944 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5037 (or 5025 counting only the distinct ones).

The product of its digits is 6912, while the sum is 29.

The square root of 642944 is about 801.8378888529. The cubic root of 642944 is about 86.3093241659.

The spelling of 642944 in words is "six hundred forty-two thousand, nine hundred forty-four".