217532070728 has 64 divisors (see below), whose sum is σ = 468676454400. Its totient is φ = 92721983040.

The previous prime is 217532070709. The next prime is 217532070731. The reversal of 217532070728 is 827070235712.

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, 8896103 + ... + 8920521.

It is an arithmetic number, because the mean of its divisors is an integer number (7323069600).

Almost surely, 2^217532070728 is an apocalyptic number.

217532070728 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

217532070728 is an abundant number, since it is smaller than the sum of its proper divisors (251144383672).

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

217532070728 is a wasteful number, since it uses less digits than its factorization.

217532070728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25290 (or 25286 counting only the distinct ones).

The product of its (nonzero) digits is 329280, while the sum is 44.

The spelling of 217532070728 in words is "two hundred seventeen billion, five hundred thirty-two million, seventy thousand, seven hundred twenty-eight".