405500640 has 96 divisors (see below), whose sum is σ = 1284304896. Its totient is φ = 107543040.

The previous prime is 405500633. The next prime is 405500647. The reversal of 405500640 is 46005504.

It is an interprime number because it is at equal distance from previous prime (405500633) and next prime (405500647).

It is a tau number, because it is divible by the number of its divisors (96).

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 405500640.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (405500647) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 89469 + ... + 93891.

It is an arithmetic number, because the mean of its divisors is an integer number (13378176).

Almost surely, 2^405500640 is an apocalyptic number.

405500640 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 405500640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (642152448).

405500640 is an abundant number, since it is smaller than the sum of its proper divisors (878804256).

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

405500640 is a wasteful number, since it uses less digits than its factorization.

405500640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4632 (or 4624 counting only the distinct ones).

The product of its (nonzero) digits is 2400, while the sum is 24.

The square root of 405500640 is about 20137.0464567175. The cubic root of 405500640 is about 740.1683571167.

The spelling of 405500640 in words is "four hundred five million, five hundred thousand, six hundred forty".