400002 has 16 divisors (see below), whose sum is σ = 806880. Its totient is φ = 132192.

The previous prime is 399989. The next prime is 400009. The reversal of 400002 is 200004.

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

It is not an unprimeable number, because it can be changed into a prime (400009) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 774 + ... + 1182.

It is an arithmetic number, because the mean of its divisors is an integer number (50430).

2⁴⁰⁰⁰⁰² is an apocalyptic number.

400002 is an abundant number, since it is smaller than the sum of its proper divisors (406878).

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

400002 is a wasteful number, since it uses less digits than its factorization.

400002 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 577.

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

The square root of 400002 is about 632.4571131705. The cubic root of 400002 is about 73.6807527737.

Adding to 400002 its reverse (200004), we get a palindrome (600006).

The spelling of 400002 in words is "four hundred thousand, two", and thus it is an iban number.