400040400 has 60 divisors (see below), whose sum is σ = 1281466592. Its totient is φ = 106677120.

The previous prime is 400040393. The next prime is 400040419. The reversal of 400040400 is 4040004.

It is a tau number, because it is divible by the number of its divisors (60).

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 congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 165484 + ... + 167883.

Almost surely, 2^400040400 is an apocalyptic number.

400040400 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

400040400 is an abundant number, since it is smaller than the sum of its proper divisors (881426192).

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

400040400 is a wasteful number, since it uses less digits than its factorization.

400040400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 333388 (or 333377 counting only the distinct ones).

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

The square root of 400040400 is about 20001.0099744988. The cubic root of 400040400 is about 736.8311047051.

Adding to 400040400 its reverse (4040004), we get a palindrome (404080404).

The spelling of 400040400 in words is "four hundred million, forty thousand, four hundred".