642560 has 40 divisors (see below), whose sum is σ = 1546776. Its totient is φ = 256000.

The previous prime is 642557. The next prime is 642563. The reversal of 642560 is 65246.

It is an interprime number because it is at equal distance from previous prime (642557) and next prime (642563).

It is a tau number, because it is divible by the number of its divisors (40).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642563) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2435 + ... + 2685.

2⁶⁴²⁵⁶⁰ 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 642560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (773388).

642560 is an abundant number, since it is smaller than the sum of its proper divisors (904216).

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

642560 is an equidigital number, since it uses as much as digits as its factorization.

642560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 274 (or 258 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 23.

The square root of 642560 is about 801.5984031920. The cubic root of 642560 is about 86.2921379200.

The spelling of 642560 in words is "six hundred forty-two thousand, five hundred sixty".