31404 has 12 divisors (see below), whose sum is σ = 73304. Its totient is φ = 10464.

The previous prime is 31397. The next prime is 31469. The reversal of 31404 is 40413.

31404 = T₇₉ + T₈₀ + ... + T₈₇.

It is a tau number, because it is divible by the number of its divisors (12).

It is a super-2 number, since 2×31404² = 1972422432, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (12), and also a Moran number because the ratio is a prime number: 2617 = 31404 / (3 + 1 + 4 + 0 + 4).

It is an Ulam number.

It is a plaindrome in base 16.

It is a nialpdrome in base 14.

It is a self number, because there is not a number n which added to its sum of digits gives 31404.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 31404.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1297 + ... + 1320.

2³¹⁴⁰⁴ is an apocalyptic number.

It is an amenable number.

31404 is an abundant number, since it is smaller than the sum of its proper divisors (41900).

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

It is a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36652).

31404 is a wasteful number, since it uses less digits than its factorization.

31404 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2624 (or 2622 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 12.

The square root of 31404 is about 177.2117377602. The cubic root of 31404 is about 31.5496822443.

Adding to 31404 its reverse (40413), we get a palindrome (71817).

Subtracting 31404 from its reverse (40413), we obtain a palindrome (9009).

It can be divided in two parts, 31 and 404, that added together give a triangular number (435 = T₂₉).

The spelling of 31404 in words is "thirty-one thousand, four hundred four".