20011001999 has 4 divisors (see below), whose sum is σ = 20015010000. Its totient is φ = 20006994000.

The previous prime is 20011001987. The next prime is 20011002007. The reversal of 20011001999 is 99910011002.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20011001999 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20011091999) 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 in 3 ways as a sum of consecutive naturals, for example, 1996502 + ... + 2006499.

It is an arithmetic number, because the mean of its divisors is an integer number (5003752500).

Almost surely, 2^20011001999 is an apocalyptic number.

20011001999 is a deficient number, since it is larger than the sum of its proper divisors (4008001).

20011001999 is an equidigital number, since it uses as much as digits as its factorization.

20011001999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4008000.

The product of its (nonzero) digits is 1458, while the sum is 32.

The spelling of 20011001999 in words is "twenty billion, eleven million, one thousand, nine hundred ninety-nine".