405216280 has 96 divisors (see below), whose sum is σ = 1074427200. Its totient is φ = 137120256.

The previous prime is 405216263. The next prime is 405216293. The reversal of 405216280 is 82612504.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is a congruent number.

It is an unprimeable number.

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 23 ways as a sum of consecutive naturals, for example, 153532 + ... + 156148.

It is an arithmetic number, because the mean of its divisors is an integer number (11191950).

Almost surely, 2^405216280 is an apocalyptic number.

405216280 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 405216280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (537213600).

405216280 is an abundant number, since it is smaller than the sum of its proper divisors (669210920).

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

405216280 is a wasteful number, since it uses less digits than its factorization.

405216280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2721 (or 2710 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 28.

The square root of 405216280 is about 20129.9846000935. The cubic root of 405216280 is about 739.9953006763.

Adding to 405216280 its reverse (82612504), we get a palindrome (487828784).

The spelling of 405216280 in words is "four hundred five million, two hundred sixteen thousand, two hundred eighty".