405740 has 12 divisors (see below), whose sum is σ = 852096. Its totient is φ = 162288.

The previous prime is 405731. The next prime is 405749. The reversal of 405740 is 47504.

405740 = T₈₅ + T₈₆ + ... + T₁₄₄.

It is an interprime number because it is at equal distance from previous prime (405731) and next prime (405749).

It is a Harshad number since it is a multiple of its sum of digits (20), and also a Moran number because the ratio is a prime number: 20287 = 405740 / (4 + 0 + 5 + 7 + 4 + 0).

It is an Ulam number.

It is a plaindrome in base 13.

It is not an unprimeable number, because it can be changed into a prime (405749) 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, 10124 + ... + 10163.

It is an arithmetic number, because the mean of its divisors is an integer number (71008).

2⁴⁰⁵⁷⁴⁰ is an apocalyptic number.

It is an amenable number.

405740 is an abundant number, since it is smaller than the sum of its proper divisors (446356).

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

405740 is a wasteful number, since it uses less digits than its factorization.

405740 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20296 (or 20294 counting only the distinct ones).

The product of its (nonzero) digits is 560, while the sum is 20.

The square root of 405740 is about 636.9772366419. The cubic root of 405740 is about 74.0313964655.

The spelling of 405740 in words is "four hundred five thousand, seven hundred forty".