401400405 has 36 divisors (see below), whose sum is σ = 809358732. Its totient is φ = 183496320.

The previous prime is 401400401. The next prime is 401400409. The reversal of 401400405 is 504004104.

It is an interprime number because it is at equal distance from previous prime (401400401) and next prime (401400409).

It can be written as a sum of positive squares in 2 ways, for example, as 106316721 + 295083684 = 10311^2 + 17178^2 .

It is not a de Polignac number, because 401400405 - 2² = 401400401 is a prime.

It is a super-2 number, since 2×401400405² = 322244570268328050, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (401400401) by changing a digit.

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 35 ways as a sum of consecutive naturals, for example, 88816 + ... + 93225.

It is an arithmetic number, because the mean of its divisors is an integer number (22482187).

Almost surely, 2^401400405 is an apocalyptic number.

401400405 is a gapful number since it is divisible by the number (45) formed by its first and last digit.

It is an amenable number.

401400405 is an abundant number, since it is smaller than the sum of its proper divisors (407958327).

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

401400405 is a wasteful number, since it uses less digits than its factorization.

401400405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 182066 (or 182056 counting only the distinct ones).

The product of its (nonzero) digits is 320, while the sum is 18.

The square root of 401400405 is about 20034.9795358019. The cubic root of 401400405 is about 737.6651542415.

Adding to 401400405 its reverse (504004104), we get a palindrome (905404509).

The spelling of 401400405 in words is "four hundred one million, four hundred thousand, four hundred five".