617987717 has 4 divisors (see below), whose sum is σ = 618229920. Its totient is φ = 617745516.

The previous prime is 617987707. The next prime is 617987719. The reversal of 617987717 is 717789716.

It is a happy number.

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 617987717 - 2¹⁶ = 617922181 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 (617987719) 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, 117233 + ... + 122390.

It is an arithmetic number, because the mean of its divisors is an integer number (154557480).

Almost surely, 2^617987717 is an apocalyptic number.

It is an amenable number.

617987717 is a deficient number, since it is larger than the sum of its proper divisors (242203).

617987717 is a wasteful number, since it uses less digits than its factorization.

617987717 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 242202.

The product of its digits is 1037232, while the sum is 53.

The square root of 617987717 is about 24859.3587407238. The cubic root of 617987717 is about 851.7783836779.

The spelling of 617987717 in words is "six hundred seventeen million, nine hundred eighty-seven thousand, seven hundred seventeen".