40040020 has 12 divisors (see below), whose sum is σ = 84084084. Its totient is φ = 16016000.

The previous prime is 40040017. The next prime is 40040027. The reversal of 40040020 is 2004004.

40040020 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 4016016 + 36024004 = 2004^2 + 6002^2 .

It is a Harshad number since it is a multiple of its sum of digits (10).

It is a junction number, because it is equal to n+sod(n) for n = 40039979 and 40040006.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40040027) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1000981 + ... + 1001020.

It is an arithmetic number, because the mean of its divisors is an integer number (7007007).

Almost surely, 2^40040020 is an apocalyptic number.

It is an amenable number.

40040020 is an abundant number, since it is smaller than the sum of its proper divisors (44044064).

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

40040020 is a wasteful number, since it uses less digits than its factorization.

40040020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2002010 (or 2002008 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 10.

The square root of 40040020 is about 6327.7183881712. The cubic root of 40040020 is about 342.1092067146.

Adding to 40040020 its reverse (2004004), we get a palindrome (42044024).

The spelling of 40040020 in words is "forty million, forty thousand, twenty".