400420404 has 36 divisors (see below), whose sum is σ = 1026436320. Its totient is φ = 131592720.

The previous prime is 400420399. The next prime is 400420411. The reversal of 400420404 is 404024004.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 75774 + ... + 80885.

It is an arithmetic number, because the mean of its divisors is an integer number (28512120).

Almost surely, 2^400420404 is an apocalyptic number.

It is an amenable number.

400420404 is an abundant number, since it is smaller than the sum of its proper divisors (626015916).

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

400420404 is a wasteful number, since it uses less digits than its factorization.

400420404 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 156740 (or 156735 counting only the distinct ones).

The product of its (nonzero) digits is 512, while the sum is 18.

The square root of 400420404 is about 20010.5073398952. The cubic root of 400420404 is about 737.0643396114.

Adding to 400420404 its reverse (404024004), we get a palindrome (804444408).

The spelling of 400420404 in words is "four hundred million, four hundred twenty thousand, four hundred four".