405540520 has 128 divisors (see below), whose sum is σ = 1143901440. Its totient is φ = 125706240.

The previous prime is 405540517. The next prime is 405540521. The reversal of 405540520 is 25045504.

It is a super-2 number, since 2×405540520² = 328926226723740800, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (405540521) 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, 1087054 + ... + 1087426.

It is an arithmetic number, because the mean of its divisors is an integer number (8936730).

Almost surely, 2^405540520 is an apocalyptic number.

405540520 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 405540520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (571950720).

405540520 is an abundant number, since it is smaller than the sum of its proper divisors (738360920).

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

405540520 is a wasteful number, since it uses less digits than its factorization.

405540520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 755 (or 751 counting only the distinct ones).

The product of its (nonzero) digits is 4000, while the sum is 25.

The square root of 405540520 is about 20138.0366471014. The cubic root of 405540520 is about 740.1926209061.

The spelling of 405540520 in words is "four hundred five million, five hundred forty thousand, five hundred twenty".