217825782420 has 48 divisors (see below), whose sum is σ = 609954222528. Its totient is φ = 58082872320.

The previous prime is 217825782413. The next prime is 217825782443. The reversal of 217825782420 is 24287528712.

It is a self number, because there is not a number n which added to its sum of digits gives 217825782420.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 810660 + ... + 1045380.

It is an arithmetic number, because the mean of its divisors is an integer number (12707379636).

Almost surely, 2^217825782420 is an apocalyptic number.

217825782420 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

217825782420 is an abundant number, since it is smaller than the sum of its proper divisors (392128440108).

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

217825782420 is a wasteful number, since it uses less digits than its factorization.

217825782420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 250200 (or 250198 counting only the distinct ones).

The product of its (nonzero) digits is 1003520, while the sum is 48.

The spelling of 217825782420 in words is "two hundred seventeen billion, eight hundred twenty-five million, seven hundred eighty-two thousand, four hundred twenty".