405442404 has 18 divisors (see below), whose sum is σ = 1024868390. Its totient is φ = 135147456.

The previous prime is 405442391. The next prime is 405442409. The reversal of 405442404 is 404244504.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 376282404 + 29160000 = 19398^2 + 5400^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a super-2 number, since 2×405442404² = 328767085922598432, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (405442409) by changing a digit.

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 5 ways as a sum of consecutive naturals, for example, 5631109 + ... + 5631180.

Almost surely, 2^405442404 is an apocalyptic number.

It is an amenable number.

405442404 is an abundant number, since it is smaller than the sum of its proper divisors (619425986).

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

405442404 is a wasteful number, since it uses less digits than its factorization.

405442404 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11262299 (or 11262294 counting only the distinct ones).

The product of its (nonzero) digits is 10240, while the sum is 27.

The square root of 405442404 is about 20135.6004131985. The cubic root of 405442404 is about 740.1329223119.

Adding to 405442404 its reverse (404244504), we get a palindrome (809686908).

The spelling of 405442404 in words is "four hundred five million, four hundred forty-two thousand, four hundred four".