42222420 has 72 divisors (see below), whose sum is σ = 129153024. Its totient is φ = 11164608.

The previous prime is 42222409. The next prime is 42222421. The reversal of 42222420 is 2422224.

42222420 is a `hidden beast` number, since 422 + 2 + 242 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 42222393 and 42222402.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42222421) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 21937 + ... + 23783.

It is an arithmetic number, because the mean of its divisors is an integer number (1793792).

Almost surely, 2^42222420 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 42222420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (64576512).

42222420 is an abundant number, since it is smaller than the sum of its proper divisors (86930604).

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

42222420 is a wasteful number, since it uses less digits than its factorization.

42222420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1989 (or 1984 counting only the distinct ones).

The product of its (nonzero) digits is 512, while the sum is 18.

The square root of 42222420 is about 6497.8781152004. The cubic root of 42222420 is about 348.2151859768.

Adding to 42222420 its reverse (2422224), we get a palindrome (44644644).

The spelling of 42222420 in words is "forty-two million, two hundred twenty-two thousand, four hundred twenty".