405090 has 48 divisors (see below), whose sum is σ = 1205568. Its totient is φ = 92448.

The previous prime is 405089. The next prime is 405091. The reversal of 405090 is 90504.

It is an interprime number because it is at equal distance from previous prime (405089) and next prime (405091).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is not an unprimeable number, because it can be changed into a prime (405091) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 309 + ... + 951.

It is an arithmetic number, because the mean of its divisors is an integer number (25116).

2⁴⁰⁵⁰⁹⁰ is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 405090, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (602784).

405090 is an abundant number, since it is smaller than the sum of its proper divisors (800478).

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

405090 is a wasteful number, since it uses less digits than its factorization.

405090 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 663 (or 660 counting only the distinct ones).

The product of its (nonzero) digits is 180, while the sum is 18.

The square root of 405090 is about 636.4668098181. The cubic root of 405090 is about 73.9918422953.

Adding to 405090 its reverse (90504), we get a palindrome (495594).

The spelling of 405090 in words is "four hundred five thousand, ninety".