400002000 has 160 divisors (see below), whose sum is σ = 1300690560. Its totient is φ = 105753600.

The previous prime is 400001951. The next prime is 400002011. The reversal of 400002000 is 200004.

It is a Harshad number since it is a multiple of its sum of digits (6).

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

It is a self number, because there is not a number n which added to its sum of digits gives 400002000.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 977796 + ... + 978204.

It is an arithmetic number, because the mean of its divisors is an integer number (8129316).

Almost surely, 2^400002000 is an apocalyptic number.

400002000 is a gapful number since it is divisible by the number (40) 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 400002000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (650345280).

400002000 is an abundant number, since it is smaller than the sum of its proper divisors (900688560).

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

400002000 is a wasteful number, since it uses less digits than its factorization.

400002000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 598 (or 582 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 6.

The square root of 400002000 is about 20000.0499999375. The cubic root of 400002000 is about 736.8075277365.

Adding to 400002000 its reverse (200004), we get a palindrome (400202004).

The spelling of 400002000 in words is "four hundred million, two thousand".