405969408 has 240 divisors, whose sum is σ = 1313728416. Its totient is φ = 124416000.

The previous prime is 405969359. The next prime is 405969433. The reversal of 405969408 is 804969504.

It is a happy number.

It is a super-2 number, since 2×405969408² = 329622320463740928, which contains 22 as substring.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1617283 + ... + 1617533.

Almost surely, 2^405969408 is an apocalyptic number.

405969408 is a gapful number since it is divisible by the number (48) 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 405969408, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (656864208).

405969408 is an abundant number, since it is smaller than the sum of its proper divisors (907759008).

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

405969408 is an equidigital number, since it uses as much as digits as its factorization.

405969408 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 297 (or 269 counting only the distinct ones).

The product of its (nonzero) digits is 311040, while the sum is 45.

The square root of 405969408 is about 20148.6825375755. The cubic root of 405969408 is about 740.4534644559.

The spelling of 405969408 in words is "four hundred five million, nine hundred sixty-nine thousand, four hundred eight".