42505020 has 48 divisors (see below), whose sum is σ = 132239520. Its totient is φ = 11334528.

The previous prime is 42505013. The next prime is 42505031. The reversal of 42505020 is 2050524.

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 = 42504984 and 42505002.

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 15 ways as a sum of consecutive naturals, for example, 38817 + ... + 39896.

It is an arithmetic number, because the mean of its divisors is an integer number (2754990).

Almost surely, 2^42505020 is an apocalyptic number.

It is an amenable number.

42505020 is an abundant number, since it is smaller than the sum of its proper divisors (89734500).

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

42505020 is a wasteful number, since it uses less digits than its factorization.

42505020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 78731 (or 78723 counting only the distinct ones).

The product of its (nonzero) digits is 400, while the sum is 18.

The square root of 42505020 is about 6519.5874102584. The cubic root of 42505020 is about 348.9903419029.

Adding to 42505020 its reverse (2050524), we get a palindrome (44555544).

The spelling of 42505020 in words is "forty-two million, five hundred five thousand, twenty".