79820208569 has 4 divisors (see below), whose sum is σ = 81173093520. Its totient is φ = 78467323620.

The previous prime is 79820208469. The next prime is 79820208577. The reversal of 79820208569 is 96580202897.

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 a de Polignac number, because none of the positive numbers 2^k-79820208569 is a prime.

It is a super-2 number, since 2×79820208569² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (79820208469) 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, 676442387 + ... + 676442504.

It is an arithmetic number, because the mean of its divisors is an integer number (20293273380).

Almost surely, 2^79820208569 is an apocalyptic number.

It is an amenable number.

79820208569 is a deficient number, since it is larger than the sum of its proper divisors (1352884951).

79820208569 is a wasteful number, since it uses less digits than its factorization.

79820208569 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1352884950.

The product of its (nonzero) digits is 4354560, while the sum is 56.

The spelling of 79820208569 in words is "seventy-nine billion, eight hundred twenty million, two hundred eight thousand, five hundred sixty-nine".