400400040 has 64 divisors (see below), whose sum is σ = 1219152960. Its totient is φ = 105177600.

The previous prime is 400399949. The next prime is 400400041. The reversal of 400400040 is 40004004.

400400040 is digitally balanced in base 6, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a super Niven number, because it is divisible the sum of any subset of its (nonzero) digits.

It is a junction number, because it is equal to n+sod(n) for n = 400399989 and 400400025.

It is not an unprimeable number, because it can be changed into a prime (400400041) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 16861 + ... + 32940.

It is an arithmetic number, because the mean of its divisors is an integer number (19049265).

Almost surely, 2^400400040 is an apocalyptic number.

400400040 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

400400040 is an abundant number, since it is smaller than the sum of its proper divisors (818752920).

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

400400040 is a wasteful number, since it uses less digits than its factorization.

400400040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 49882 (or 49878 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 12.

The square root of 400400040 is about 20009.9985007496. The cubic root of 400400040 is about 737.0518445499.

Adding to 400400040 its reverse (40004004), we get a palindrome (440404044).

The spelling of 400400040 in words is "four hundred million, four hundred thousand, forty".