216251970841 has 9 divisors (see below), whose sum is σ = 217782846813. Its totient is φ = 214731791040.

The previous prime is 216251970811. The next prime is 216251970853. The reversal of 216251970841 is 148079152612.

The square root of 216251970841 is 465029.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 187290738441 + 28961232400 = 432771^2 + 170180^2 .

It is not a de Polignac number, because 216251970841 - 2¹³ = 216251962649 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 216251970791 and 216251970800.

It is not an unprimeable number, because it can be changed into a prime (216251970811) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 69287761 + ... + 69290881.

Almost surely, 2^216251970841 is an apocalyptic number.

216251970841 is the 465029-th square number.

216251970841 is the 232515-th centered octagonal number.

It is an amenable number.

216251970841 is a deficient number, since it is larger than the sum of its proper divisors (1530875972).

216251970841 is an frugal number, since it uses more digits than its factorization.

216251970841 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6540 (or 3270 counting only the distinct ones).

The product of its (nonzero) digits is 241920, while the sum is 46.

The spelling of 216251970841 in words is "two hundred sixteen billion, two hundred fifty-one million, nine hundred seventy thousand, eight hundred forty-one".