79878487897 has 4 divisors (see below), whose sum is σ = 86022986980. Its totient is φ = 73733988816.

The previous prime is 79878487889. The next prime is 79878487907.

79878487897 is nontrivially palindromic in base 10.

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 30100862016 + 49777625881 = 173496^2 + 223109^2 .

It is a cyclic number.

It is not a de Polignac number, because 79878487897 - 2³ = 79878487889 is a prime.

It is a super-2 number, since 2×79878487897² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 79878487897.

It is not an unprimeable number, because it can be changed into a prime (79878487847) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3072249522 + ... + 3072249547.

It is an arithmetic number, because the mean of its divisors is an integer number (21505746745).

Almost surely, 2^79878487897 is an apocalyptic number.

It is an amenable number.

79878487897 is a deficient number, since it is larger than the sum of its proper divisors (6144499083).

79878487897 is a wasteful number, since it uses less digits than its factorization.

79878487897 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6144499082.

The product of its digits is 3186376704, while the sum is 82.

The spelling of 79878487897 in words is "seventy-nine billion, eight hundred seventy-eight million, four hundred eighty-seven thousand, eight hundred ninety-seven".