216575601281 has 4 divisors (see below), whose sum is σ = 233235262932. Its totient is φ = 199915939632.

The previous prime is 216575601197. The next prime is 216575601331. The reversal of 216575601281 is 182106575612.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 13679407681 + 202896193600 = 116959^2 + 450440^2 .

It is a cyclic number.

It is not a de Polignac number, because 216575601281 - 2³⁰ = 215501859457 is a prime.

It is a super-2 number, since 2×216575601281² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (216575604281) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8329830806 + ... + 8329830831.

It is an arithmetic number, because the mean of its divisors is an integer number (58308815733).

Almost surely, 2^216575601281 is an apocalyptic number.

It is an amenable number.

216575601281 is a deficient number, since it is larger than the sum of its proper divisors (16659661651).

216575601281 is a wasteful number, since it uses less digits than its factorization.

216575601281 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16659661650.

The product of its (nonzero) digits is 201600, while the sum is 44.

The spelling of 216575601281 in words is "two hundred sixteen billion, five hundred seventy-five million, six hundred one thousand, two hundred eighty-one".