997641847879 has 2 divisors, whose sum is σ = 997641847880. Its totient is φ = 997641847878.

The previous prime is 997641847861. The next prime is 997641847907. The reversal of 997641847879 is 978748146799.

It is a weak prime.

It is an emirp because it is prime and its reverse (978748146799) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 997641847879 - 2¹¹ = 997641845831 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 997641847799 and 997641847808.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (997641841879) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 498820923939 + 498820923940.

It is an arithmetic number, because the mean of its divisors is an integer number (498820923940).

Almost surely, 2^997641847879 is an apocalyptic number.

997641847879 is a deficient number, since it is larger than the sum of its proper divisors (1).

997641847879 is an equidigital number, since it uses as much as digits as its factorization.

997641847879 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1536288768, while the sum is 79.

The spelling of 997641847879 in words is "nine hundred ninety-seven billion, six hundred forty-one million, eight hundred forty-seven thousand, eight hundred seventy-nine".