400181 has 4 divisors (see below), whose sum is σ = 403200. Its totient is φ = 397164.

The previous prime is 400157. The next prime is 400187. The reversal of 400181 is 181004.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 400181 - 2¹⁴ = 383797 is a prime.

It is a super-2 number, since 2×400181² = 320289665522, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 400181.

It is not an unprimeable number, because it can be changed into a prime (400187) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1301 + ... + 1578.

It is an arithmetic number, because the mean of its divisors is an integer number (100800).

2⁴⁰⁰¹⁸¹ is an apocalyptic number.

It is an amenable number.

400181 is a deficient number, since it is larger than the sum of its proper divisors (3019).

400181 is a wasteful number, since it uses less digits than its factorization.

400181 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3018.

The product of its (nonzero) digits is 32, while the sum is 14.

The square root of 400181 is about 632.5986089141. The cubic root of 400181 is about 73.6917417920.

Adding to 400181 its reverse (181004), we get a palindrome (581185).

The spelling of 400181 in words is "four hundred thousand, one hundred eighty-one".