42112820 has 12 divisors (see below), whose sum is σ = 88436964. Its totient is φ = 16845120.

The previous prime is 42112817. The next prime is 42112879. The reversal of 42112820 is 2821124.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 29181604 + 12931216 = 5402^2 + 3596^2 .

It is a Harshad number since it is a multiple of its sum of digits (20), and also a Moran number because the ratio is a prime number: 2105641 = 42112820 / (4 + 2 + 1 + 1 + 2 + 8 + 2 + 0).

It is a junction number, because it is equal to n+sod(n) for n = 42112792 and 42112801.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1052801 + ... + 1052840.

It is an arithmetic number, because the mean of its divisors is an integer number (7369747).

Almost surely, 2^42112820 is an apocalyptic number.

It is an amenable number.

42112820 is an abundant number, since it is smaller than the sum of its proper divisors (46324144).

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

42112820 is a wasteful number, since it uses less digits than its factorization.

42112820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2105650 (or 2105648 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 20.

The square root of 42112820 is about 6489.4391128972. The cubic root of 42112820 is about 347.9136285407.

Adding to 42112820 its reverse (2821124), we get a palindrome (44933944).

The spelling of 42112820 in words is "forty-two million, one hundred twelve thousand, eight hundred twenty".