400971 has 4 divisors (see below), whose sum is σ = 534632. Its totient is φ = 267312.

The previous prime is 400963. The next prime is 400997. The reversal of 400971 is 179004.

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

It is not a de Polignac number, because 400971 - 2³ = 400963 is a prime.

It is a D-number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (400931) 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, 66826 + ... + 66831.

It is an arithmetic number, because the mean of its divisors is an integer number (133658).

2⁴⁰⁰⁹⁷¹ is an apocalyptic number.

400971 is a deficient number, since it is larger than the sum of its proper divisors (133661).

400971 is a wasteful number, since it uses less digits than its factorization.

400971 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 133660.

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

The square root of 400971 is about 633.2227096370. Note that the first 3 decimals coincide. The cubic root of 400971 is about 73.7402017051.

Adding to 400971 its reverse (179004), we get a palindrome (579975).

The spelling of 400971 in words is "four hundred thousand, nine hundred seventy-one".