642320 has 80 divisors (see below), whose sum is σ = 1809408. Its totient is φ = 207360.

The previous prime is 642281. The next prime is 642359. The reversal of 642320 is 23246.

642320 is nontrivially palindromic in base 6.

It is an interprime number because it is at equal distance from previous prime (642281) and next prime (642359).

It is a tau number, because it is divible by the number of its divisors (80).

It is an unprimeable number.

642320 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 17342 + ... + 17378.

2⁶⁴²³²⁰ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 642320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (904704).

642320 is an abundant number, since it is smaller than the sum of its proper divisors (1167088).

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

642320 is a wasteful number, since it uses less digits than its factorization.

642320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 88 (or 82 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 17.

The square root of 642320 is about 801.4486883139. The cubic root of 642320 is about 86.2813930391.

Adding to 642320 its reverse (23246), we get a palindrome (665566).

The spelling of 642320 in words is "six hundred forty-two thousand, three hundred twenty".