215725680 has 200 divisors, whose sum is σ = 757822032. Its totient is φ = 57106944.

The previous prime is 215725603. The next prime is 215725681. The reversal of 215725680 is 86527512.

It is a happy number.

215725680 is a `hidden beast` number, since 2 + 1 + 572 + 5 + 6 + 80 = 666.

It is a super-2 number, since 2×215725680² = 93075138022924800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (215725681) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 1574572 + ... + 1574708.

Almost surely, 2^215725680 is an apocalyptic number.

215725680 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 215725680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (378911016).

215725680 is an abundant number, since it is smaller than the sum of its proper divisors (542096352).

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

215725680 is an frugal number, since it uses more digits than its factorization.

215725680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 177 (or 147 counting only the distinct ones).

The product of its (nonzero) digits is 33600, while the sum is 36.

The square root of 215725680 is about 14687.6029358095. The cubic root of 215725680 is about 599.7458923974.

The spelling of 215725680 in words is "two hundred fifteen million, seven hundred twenty-five thousand, six hundred eighty".