20901887999 has 2 divisors, whose sum is σ = 20901888000. Its totient is φ = 20901887998.

The previous prime is 20901887989. The next prime is 20901888001. The reversal of 20901887999 is 99978810902.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20901887999 - 2²⁰ = 20900839423 is a prime.

Together with 20901888001, 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 (20901887969) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10450943999 + 10450944000.

It is an arithmetic number, because the mean of its divisors is an integer number (10450944000).

Almost surely, 2^20901887999 is an apocalyptic number.

20901887999 is a deficient number, since it is larger than the sum of its proper divisors (1).

20901887999 is an equidigital number, since it uses as much as digits as its factorization.

20901887999 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5878656, while the sum is 62.

The spelling of 20901887999 in words is "twenty billion, nine hundred one million, eight hundred eighty-seven thousand, nine hundred ninety-nine".