400281 has 16 divisors (see below), whose sum is σ = 624000. Its totient is φ = 228144.

The previous prime is 400277. The next prime is 400291. The reversal of 400281 is 182004.

It is not a de Polignac number, because 400281 - 2² = 400277 is a prime.

It is a super-2 number, since 2×400281² = 320449757922, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 400281.

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 400281.

It is not an unprimeable number, because it can be changed into a prime (400261) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 835 + ... + 1223.

It is an arithmetic number, because the mean of its divisors is an integer number (39000).

2⁴⁰⁰²⁸¹ is an apocalyptic number.

It is an amenable number.

400281 is a deficient number, since it is larger than the sum of its proper divisors (223719).

400281 is an equidigital number, since it uses as much as digits as its factorization.

400281 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 413 (or 399 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 15.

The square root of 400281 is about 632.6776430379. The cubic root of 400281 is about 73.6978794817.

Adding to 400281 its reverse (182004), we get a palindrome (582285).

The spelling of 400281 in words is "four hundred thousand, two hundred eighty-one".