20001998016797 has 2 divisors, whose sum is σ = 20001998016798. Its totient is φ = 20001998016796.

The previous prime is 20001998016719. The next prime is 20001998016799. The reversal of 20001998016797 is 79761089910002.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14610657667321 + 5391340349476 = 3822389^2 + 2321926^2 .

It is a cyclic number.

It is not a de Polignac number, because 20001998016797 - 2¹⁶ = 20001997951261 is a prime.

It is a super-2 number, since 2×20001998016797² (a number of 27 digits) contains 22 as substring.

Together with 20001998016799, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20001998016799) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10000999008398 + 10000999008399.

It is an arithmetic number, because the mean of its divisors is an integer number (10000999008399).

Almost surely, 2^{20001998016797} is an apocalyptic number.

It is an amenable number.

20001998016797 is a deficient number, since it is larger than the sum of its proper divisors (1).

20001998016797 is an equidigital number, since it uses as much as digits as its factorization.

20001998016797 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3429216, while the sum is 59.

The spelling of 20001998016797 in words is "twenty trillion, one billion, nine hundred ninety-eight million, sixteen thousand, seven hundred ninety-seven".