217970479679 has 4 divisors (see below), whose sum is σ = 217977920280. Its totient is φ = 217963039080.

The previous prime is 217970479619. The next prime is 217970479687. The reversal of 217970479679 is 976974079712.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 217970479679 - 2²⁰ = 217969431103 is a prime.

It is a super-2 number, since 2×217970479679² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (217970479619) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3676184 + ... + 3735005.

It is an arithmetic number, because the mean of its divisors is an integer number (54494480070).

Almost surely, 2^217970479679 is an apocalyptic number.

217970479679 is a deficient number, since it is larger than the sum of its proper divisors (7440601).

217970479679 is an equidigital number, since it uses as much as digits as its factorization.

217970479679 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7440600.

The product of its (nonzero) digits is 84015792, while the sum is 68.

The spelling of 217970479679 in words is "two hundred seventeen billion, nine hundred seventy million, four hundred seventy-nine thousand, six hundred seventy-nine".