217011157 has 4 divisors (see below), whose sum is σ = 236739456. Its totient is φ = 197282860.

The previous prime is 217011139. The next prime is 217011161. The reversal of 217011157 is 751110712.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 217011157 - 2¹¹ = 217009109 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (217011127) 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, 9864133 + ... + 9864154.

It is an arithmetic number, because the mean of its divisors is an integer number (59184864).

Almost surely, 2^217011157 is an apocalyptic number.

It is an amenable number.

217011157 is a deficient number, since it is larger than the sum of its proper divisors (19728299).

217011157 is a wasteful number, since it uses less digits than its factorization.

217011157 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19728298.

The product of its (nonzero) digits is 490, while the sum is 25.

The square root of 217011157 is about 14731.2985510443. The cubic root of 217011157 is about 600.9347993089.

Adding to 217011157 its reverse (751110712), we get a palindrome (968121869).

The spelling of 217011157 in words is "two hundred seventeen million, eleven thousand, one hundred fifty-seven".