642220 has 24 divisors (see below), whose sum is σ = 1363824. Its totient is φ = 254016.

The previous prime is 642217. The next prime is 642223. The reversal of 642220 is 22246.

642220 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (642217) and next prime (642223).

It is a nialpdrome in base 10.

It is a junction number, because it is equal to n+sod(n) for n = 642194 and 642203.

It is not an unprimeable number, because it can be changed into a prime (642223) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3162 + ... + 3358.

It is an arithmetic number, because the mean of its divisors is an integer number (56826).

2⁶⁴²²²⁰ is an apocalyptic number.

It is an amenable number.

642220 is an abundant number, since it is smaller than the sum of its proper divisors (721604).

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

642220 is a wasteful number, since it uses less digits than its factorization.

642220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 369 (or 367 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 16.

The square root of 642220 is about 801.3862988597. The cubic root of 642220 is about 86.2769152154.

Adding to 642220 its reverse (22246), we get a palindrome (664466).

The spelling of 642220 in words is "six hundred forty-two thousand, two hundred twenty".