20121020999 has 2 divisors, whose sum is σ = 20121021000. Its totient is φ = 20121020998.

The previous prime is 20121020951. The next prime is 20121021001. The reversal of 20121020999 is 99902012102.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20121020999 is a prime.

Together with 20121021001, 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 (20121028999) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10060510499 + 10060510500.

It is an arithmetic number, because the mean of its divisors is an integer number (10060510500).

Almost surely, 2^20121020999 is an apocalyptic number.

20121020999 is a deficient number, since it is larger than the sum of its proper divisors (1).

20121020999 is an equidigital number, since it uses as much as digits as its factorization.

20121020999 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5832, while the sum is 35.

The spelling of 20121020999 in words is "twenty billion, one hundred twenty-one million, twenty thousand, nine hundred ninety-nine".