405797820 has 96 divisors (see below), whose sum is σ = 1266451200. Its totient is φ = 96482304.

The previous prime is 405797813. The next prime is 405797827. The reversal of 405797820 is 28797504.

It is an interprime number because it is at equal distance from previous prime (405797813) and next prime (405797827).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (405797827) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 8911 + ... + 29849.

It is an arithmetic number, because the mean of its divisors is an integer number (13192200).

Almost surely, 2^405797820 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 405797820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (633225600).

405797820 is an abundant number, since it is smaller than the sum of its proper divisors (860653380).

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

405797820 is a wasteful number, since it uses less digits than its factorization.

405797820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20987 (or 20985 counting only the distinct ones).

The product of its (nonzero) digits is 141120, while the sum is 42.

The square root of 405797820 is about 20144.4240423994. The cubic root of 405797820 is about 740.3491291448.

The spelling of 405797820 in words is "four hundred five million, seven hundred ninety-seven thousand, eight hundred twenty".