20001001999997 has 2 divisors, whose sum is σ = 20001001999998. Its totient is φ = 20001001999996.

The previous prime is 20001001999981. The next prime is 20001002000027. The reversal of 20001001999997 is 79999910010002.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17345109244516 + 2655892755481 = 4164746^2 + 1629691^2 .

It is a cyclic number.

It is not a de Polignac number, because 20001001999997 - 2⁴ = 20001001999981 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20001001999597) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10000500999998 + 10000500999999.

It is an arithmetic number, because the mean of its divisors is an integer number (10000500999999).

Almost surely, 2^{20001001999997} is an apocalyptic number.

It is an amenable number.

20001001999997 is a deficient number, since it is larger than the sum of its proper divisors (1).

20001001999997 is an equidigital number, since it uses as much as digits as its factorization.

20001001999997 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 826686, while the sum is 56.

The spelling of 20001001999997 in words is "twenty trillion, one billion, one million, nine hundred ninety-nine thousand, nine hundred ninety-seven".