400240 has 20 divisors (see below), whose sum is σ = 930744. Its totient is φ = 160064.

The previous prime is 400237. The next prime is 400243. The reversal of 400240 is 42004.

It is an interprime number because it is at equal distance from previous prime (400237) and next prime (400243).

It is a tau number, because it is divible by the number of its divisors (20).

It is a Harshad number since it is a multiple of its sum of digits (10).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (400243) 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, 2422 + ... + 2581.

2⁴⁰⁰²⁴⁰ is an apocalyptic number.

400240 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

400240 is an abundant number, since it is smaller than the sum of its proper divisors (530504).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

400240 is a wasteful number, since it uses less digits than its factorization.

400240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5016 (or 5010 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 10.

The square root of 400240 is about 632.6452402413. The cubic root of 400240 is about 73.6953631526.

Adding to 400240 its reverse (42004), we get a palindrome (442244).

The spelling of 400240 in words is "four hundred thousand, two hundred forty", and thus it is an iban number.