4020400040 has 32 divisors (see below), whose sum is σ = 9578013480. Its totient is φ = 1513562112.

The previous prime is 4020400039. The next prime is 4020400049. The reversal of 4020400040 is 400040204.

It can be written as a sum of positive squares in 4 ways, for example, as 3796777924 + 223622116 = 61618^2 + 14954^2 .

It is a junction number, because it is equal to n+sod(n) for n = 4020399988 and 4020400024.

It is not an unprimeable number, because it can be changed into a prime (4020400049) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2955497 + ... + 2956856.

Almost surely, 2^4020400040 is an apocalyptic number.

4020400040 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

4020400040 is an abundant number, since it is smaller than the sum of its proper divisors (5557613440).

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

4020400040 is a wasteful number, since it uses less digits than its factorization.

4020400040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5912381 (or 5912377 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 14.

The square root of 4020400040 is about 63406.6245750395. The cubic root of 4020400040 is about 1590.0950643951.

Adding to 4020400040 its reverse (400040204), we get a palindrome (4420440244).

The spelling of 4020400040 in words is "four billion, twenty million, four hundred thousand, forty".