42820020 has 72 divisors (see below), whose sum is σ = 135547776. Its totient is φ = 10921152.

The previous prime is 42820013. The next prime is 42820033. The reversal of 42820020 is 2002824.

It is a super-2 number, since 2×42820020² = 3667108225600800, which contains 22 as substring.

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 = 42819975 and 42820002.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1032 + ... + 9311.

It is an arithmetic number, because the mean of its divisors is an integer number (1882608).

Almost surely, 2^42820020 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 42820020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (67773888).

42820020 is an abundant number, since it is smaller than the sum of its proper divisors (92727756).

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

42820020 is a wasteful number, since it uses less digits than its factorization.

42820020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10381 (or 10376 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 18.

The square root of 42820020 is about 6543.7007877806. The cubic root of 42820020 is about 349.8503305643.

Adding to 42820020 its reverse (2002824), we get a palindrome (44822844).

The spelling of 42820020 in words is "forty-two million, eight hundred twenty thousand, twenty".