400981 has 4 divisors (see below), whose sum is σ = 458272. Its totient is φ = 343692.

The previous prime is 400963. The next prime is 400997. The reversal of 400981 is 189004.

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 400981 - 2⁵ = 400949 is a prime.

It is a super-2 number, since 2×400981² = 321571524722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent 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, 28635 + ... + 28648.

It is an arithmetic number, because the mean of its divisors is an integer number (114568).

2⁴⁰⁰⁹⁸¹ is an apocalyptic number.

It is an amenable number.

400981 is a deficient number, since it is larger than the sum of its proper divisors (57291).

400981 is an equidigital number, since it uses as much as digits as its factorization.

400981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57290.

The product of its (nonzero) digits is 288, while the sum is 22.

The square root of 400981 is about 633.2306057038. The cubic root of 400981 is about 73.7408147136.

Adding to 400981 its reverse (189004), we get a palindrome (589985).

The spelling of 400981 in words is "four hundred thousand, nine hundred eighty-one".