400639008 has 192 divisors, whose sum is σ = 1329011712. Its totient is φ = 102650880.

The previous prime is 400638989. The next prime is 400639021. The reversal of 400639008 is 800936004.

It is a super-2 number, since 2×400639008² = 321023229462448128, which contains 22 as substring.

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 31 ways as a sum of consecutive naturals, for example, 613210 + ... + 613862.

It is an arithmetic number, because the mean of its divisors is an integer number (6921936).

Almost surely, 2^400639008 is an apocalyptic number.

400639008 is a gapful number since it is divisible by the number (48) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 400639008, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (664505856).

400639008 is an abundant number, since it is smaller than the sum of its proper divisors (928372704).

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

400639008 is a wasteful number, since it uses less digits than its factorization.

400639008 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 767 (or 759 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 30.

The square root of 400639008 is about 20015.9688249158. The cubic root of 400639008 is about 737.1984452487.

The spelling of 400639008 in words is "four hundred million, six hundred thirty-nine thousand, eight".