40008020 has 24 divisors (see below), whose sum is σ = 90480264. Its totient is φ = 14772096.

The previous prime is 40008013. The next prime is 40008029. The reversal of 40008020 is 2080004.

It can be written as a sum of positive squares in 4 ways, for example, as 217156 + 39790864 = 466^2 + 6308^2 .

It is a junction number, because it is equal to n+sod(n) for n = 40007986 and 40008004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40008029) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 76679 + ... + 77198.

It is an arithmetic number, because the mean of its divisors is an integer number (3770011).

Almost surely, 2^40008020 is an apocalyptic number.

It is an amenable number.

40008020 is an abundant number, since it is smaller than the sum of its proper divisors (50472244).

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

40008020 is a wasteful number, since it uses less digits than its factorization.

40008020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 153899 (or 153897 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 14.

The square root of 40008020 is about 6325.1893252297. The cubic root of 40008020 is about 342.0180444864.

Adding to 40008020 its reverse (2080004), we get a palindrome (42088024).

The spelling of 40008020 in words is "forty million, eight thousand, twenty".