215971072 has 54 divisors (see below), whose sum is σ = 445701354. Its totient is φ = 104371200.

The previous prime is 215971061. The next prime is 215971073. The reversal of 215971072 is 270179512.

215971072 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 210134016 + 5837056 = 14496^2 + 2416^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (215971073) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1430197 + ... + 1430347.

Almost surely, 2^215971072 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 215971072, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (222850677).

215971072 is an abundant number, since it is smaller than the sum of its proper divisors (229730282).

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

215971072 is an frugal number, since it uses more digits than its factorization.

215971072 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 355 (or 190 counting only the distinct ones).

The product of its (nonzero) digits is 8820, while the sum is 34.

The square root of 215971072 is about 14695.9542732005. The cubic root of 215971072 is about 599.9732136190.

The spelling of 215971072 in words is "two hundred fifteen million, nine hundred seventy-one thousand, seventy-two".