400861 has 8 divisors (see below), whose sum is σ = 422144. Its totient is φ = 380160.

The previous prime is 400859. The next prime is 400871. The reversal of 400861 is 168004.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 400861 - 2¹ = 400859 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (400871) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1981 + ... + 2173.

It is an arithmetic number, because the mean of its divisors is an integer number (52768).

2⁴⁰⁰⁸⁶¹ is an apocalyptic number.

It is an amenable number.

400861 is a deficient number, since it is larger than the sum of its proper divisors (21283).

400861 is a wasteful number, since it uses less digits than its factorization.

400861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 291.

The product of its (nonzero) digits is 192, while the sum is 19.

The square root of 400861 is about 633.1358464026. The cubic root of 400861 is about 73.7334579389.

Adding to 400861 its reverse (168004), we get a palindrome (568865).

The spelling of 400861 in words is "four hundred thousand, eight hundred sixty-one".