400791 has 4 divisors (see below), whose sum is σ = 534392. Its totient is φ = 267192.

The previous prime is 400759. The next prime is 400823. The reversal of 400791 is 197004.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (400759) and next prime (400823).

It is not a de Polignac number, because 400791 - 2⁵ = 400759 is a prime.

It is a D-number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (400711) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 66796 + ... + 66801.

It is an arithmetic number, because the mean of its divisors is an integer number (133598).

2⁴⁰⁰⁷⁹¹ is an apocalyptic number.

400791 is a deficient number, since it is larger than the sum of its proper divisors (133601).

400791 is a wasteful number, since it uses less digits than its factorization.

400791 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 133600.

The product of its (nonzero) digits is 252, while the sum is 21.

The square root of 400791 is about 633.0805635936. The cubic root of 400791 is about 73.7291658089.

Adding to 400791 its reverse (197004), we get a palindrome (597795).

The spelling of 400791 in words is "four hundred thousand, seven hundred ninety-one".