215840000 has 180 divisors, whose sum is σ = 574691040. Its totient is φ = 80640000.

The previous prime is 215839997. The next prime is 215840017. The reversal of 215840000 is 48512.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a congruent number.

It is an unprimeable number.

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 19 ways as a sum of consecutive naturals, for example, 3039965 + ... + 3040035.

It is an arithmetic number, because the mean of its divisors is an integer number (3192728).

Almost surely, 2^215840000 is an apocalyptic number.

215840000 is a gapful number since it is divisible by the number (20) 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 215840000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (287345520).

215840000 is an abundant number, since it is smaller than the sum of its proper divisors (358851040).

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

215840000 is an frugal number, since it uses more digits than its factorization.

215840000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 126 (or 97 counting only the distinct ones).

The product of its (nonzero) digits is 320, while the sum is 20.

The square root of 215840000 is about 14691.4941377656. The cubic root of 215840000 is about 599.8518152570.

Adding to 215840000 its reverse (48512), we get a palindrome (215888512).

The spelling of 215840000 in words is "two hundred fifteen million, eight hundred forty thousand".