997879 has 2 divisors, whose sum is σ = 997880. Its totient is φ = 997878.

The previous prime is 997877. The next prime is 997889. The reversal of 997879 is 978799.

It is a weak prime.

It is an emirp because it is prime and its reverse (978799) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 997879 - 2¹ = 997877 is a prime.

Together with 997877, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (997877) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 498939 + 498940.

It is an arithmetic number, because the mean of its divisors is an integer number (498940).

2⁹⁹⁷⁸⁷⁹ is an apocalyptic number.

997879 is a deficient number, since it is larger than the sum of its proper divisors (1).

997879 is an equidigital number, since it uses as much as digits as its factorization.

997879 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 285768, while the sum is 49.

The square root of 997879 is about 998.9389370727. The cubic root of 997879 is about 99.9292499561.

The spelling of 997879 in words is "nine hundred ninety-seven thousand, eight hundred seventy-nine".