998223121897 has 2 divisors, whose sum is σ = 998223121898. Its totient is φ = 998223121896.

The previous prime is 998223121751. The next prime is 998223121913. The reversal of 998223121897 is 798121322899.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 595329523776 + 402893598121 = 771576^2 + 634739^2 .

It is a cyclic number.

It is not a de Polignac number, because 998223121897 - 2¹⁹ = 998222597609 is a prime.

It is not a weakly prime, because it can be changed into another prime (998223121697) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 499111560948 + 499111560949.

It is an arithmetic number, because the mean of its divisors is an integer number (499111560949).

Almost surely, 2^998223121897 is an apocalyptic number.

It is an amenable number.

998223121897 is a deficient number, since it is larger than the sum of its proper divisors (1).

998223121897 is an equidigital number, since it uses as much as digits as its factorization.

998223121897 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 7838208, while the sum is 61.

The spelling of 998223121897 in words is "nine hundred ninety-eight billion, two hundred twenty-three million, one hundred twenty-one thousand, eight hundred ninety-seven".