197878424878279 has 2 divisors, whose sum is σ = 197878424878280. Its totient is φ = 197878424878278.

The previous prime is 197878424878237. The next prime is 197878424878327. The reversal of 197878424878279 is 972878424878791.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 197878424878279 - 2⁴⁵ = 162694052789447 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 197878424878193 and 197878424878202.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (197878424875279) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 98939212439139 + 98939212439140.

It is an arithmetic number, because the mean of its divisors is an integer number (98939212439140).

Almost surely, 2^{197878424878279} is an apocalyptic number.

197878424878279 is a deficient number, since it is larger than the sum of its proper divisors (1).

197878424878279 is an equidigital number, since it uses as much as digits as its factorization.

197878424878279 is an evil number, because the sum of its binary digits is even.

The product of its digits is 50982027264, while the sum is 91.

The spelling of 197878424878279 in words is "one hundred ninety-seven trillion, eight hundred seventy-eight billion, four hundred twenty-four million, eight hundred seventy-eight thousand, two hundred seventy-nine".