402405 has 16 divisors (see below), whose sum is σ = 651840. Its totient is φ = 211968.

The previous prime is 402403. The next prime is 402419. The reversal of 402405 is 504204.

It is not a de Polignac number, because 402405 - 2¹ = 402403 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (15).

402405 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (402403) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1989 + ... + 2181.

It is an arithmetic number, because the mean of its divisors is an integer number (40740).

2⁴⁰²⁴⁰⁵ is an apocalyptic number.

It is an amenable number.

402405 is a deficient number, since it is larger than the sum of its proper divisors (249435).

402405 is a wasteful number, since it uses less digits than its factorization.

402405 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 340.

The product of its (nonzero) digits is 160, while the sum is 15.

The square root of 402405 is about 634.3540021155. The cubic root of 402405 is about 73.8280032682.

Multiplying 402405 by its sum of digits (15), we get a triangular number (6036075 = T₃₄₇₄).

Adding to 402405 its reverse (504204), we get a palindrome (906609).

The spelling of 402405 in words is "four hundred two thousand, four hundred five".