405401280 has 112 divisors (see below), whose sum is σ = 1295119584. Its totient is φ = 107438080.

The previous prime is 405401257. The next prime is 405401281. The reversal of 405401280 is 82104504.

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 405401280.

It is not an unprimeable number, because it can be changed into a prime (405401281) 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, 164860 + ... + 167300.

Almost surely, 2^405401280 is an apocalyptic number.

405401280 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 405401280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (647559792).

405401280 is an abundant number, since it is smaller than the sum of its proper divisors (889718304).

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

405401280 is a wasteful number, since it uses less digits than its factorization.

405401280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2634 (or 2624 counting only the distinct ones).

The product of its (nonzero) digits is 1280, while the sum is 24.

The square root of 405401280 is about 20134.5792108998. The cubic root of 405401280 is about 740.1078975857.

Adding to 405401280 its reverse (82104504), we get a palindrome (487505784).

The spelling of 405401280 in words is "four hundred five million, four hundred one thousand, two hundred eighty".