20000212021991 has 2 divisors, whose sum is σ = 20000212021992. Its totient is φ = 20000212021990.

The previous prime is 20000212021987. The next prime is 20000212022003. The reversal of 20000212021991 is 19912021200002.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20000212021991 - 2² = 20000212021987 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20000212023991) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10000106010995 + 10000106010996.

It is an arithmetic number, because the mean of its divisors is an integer number (10000106010996).

Almost surely, 2^{20000212021991} is an apocalyptic number.

20000212021991 is a deficient number, since it is larger than the sum of its proper divisors (1).

20000212021991 is an equidigital number, since it uses as much as digits as its factorization.

20000212021991 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1296, while the sum is 29.

Adding to 20000212021991 its reverse (19912021200002), we get a palindrome (39912233221993).

The spelling of 20000212021991 in words is "twenty trillion, two hundred twelve million, twenty-one thousand, nine hundred ninety-one".