405540389 has 32 divisors (see below), whose sum is σ = 468840960. Its totient is φ = 348364800.

The previous prime is 405540349. The next prime is 405540397. The reversal of 405540389 is 983045504.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 405540389 - 2⁸ = 405540133 is a prime.

It is a super-2 number, since 2×405540389² = 328926014220542642, which contains 22 as substring.

It is a Smith number, since the sum of its digits (38) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (405540349) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1496324 + ... + 1496594.

It is an arithmetic number, because the mean of its divisors is an integer number (14651280).

Almost surely, 2^405540389 is an apocalyptic number.

It is an amenable number.

405540389 is a deficient number, since it is larger than the sum of its proper divisors (63300571).

405540389 is a wasteful number, since it uses less digits than its factorization.

405540389 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 461.

The product of its (nonzero) digits is 86400, while the sum is 38.

The square root of 405540389 is about 20138.0333945497. The cubic root of 405540389 is about 740.1925412057.

It can be divided in two parts, 4055 and 40389, that added together give a palindrome (44444).

The spelling of 405540389 in words is "four hundred five million, five hundred forty thousand, three hundred eighty-nine".