217480913 has 4 divisors (see below), whose sum is σ = 234210228. Its totient is φ = 200751600.

The previous prime is 217480877. The next prime is 217480937. The reversal of 217480913 is 319084712.

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 15499969 + 201980944 = 3937^2 + 14212^2 .

It is a cyclic number.

It is not a de Polignac number, because 217480913 - 2¹² = 217476817 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (217480993) 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, 8364638 + ... + 8364663.

It is an arithmetic number, because the mean of its divisors is an integer number (58552557).

Almost surely, 2^217480913 is an apocalyptic number.

It is an amenable number.

217480913 is a deficient number, since it is larger than the sum of its proper divisors (16729315).

217480913 is a wasteful number, since it uses less digits than its factorization.

217480913 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16729314.

The product of its (nonzero) digits is 12096, while the sum is 35.

The square root of 217480913 is about 14747.2340796503. The cubic root of 217480913 is about 601.3680939016.

The spelling of 217480913 in words is "two hundred seventeen million, four hundred eighty thousand, nine hundred thirteen".