405475840 has 320 divisors, whose sum is σ = 1293988608. Its totient is φ = 118947840.

The previous prime is 405475831. The next prime is 405475849. The reversal of 405475840 is 48574504.

It is an interprime number because it is at equal distance from previous prime (405475831) and next prime (405475849).

It is a tau number, because it is divible by the number of its divisors (320).

It is a self number, because there is not a number n which added to its sum of digits gives 405475840.

It is not an unprimeable number, because it can be changed into a prime (405475849) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 23851512 + ... + 23851528.

Almost surely, 2^405475840 is an apocalyptic number.

405475840 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 405475840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (646994304).

405475840 is an abundant number, since it is smaller than the sum of its proper divisors (888512768).

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

405475840 is an equidigital number, since it uses as much as digits as its factorization.

405475840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80 (or 42 counting only the distinct ones).

The product of its (nonzero) digits is 89600, while the sum is 37.

The square root of 405475840 is about 20136.4306668287. The cubic root of 405475840 is about 740.1532674985.

The spelling of 405475840 in words is "four hundred five million, four hundred seventy-five thousand, eight hundred forty".