21000211201939 has 2 divisors, whose sum is σ = 21000211201940. Its totient is φ = 21000211201938.

The previous prime is 21000211201841. The next prime is 21000211202041. The reversal of 21000211201939 is 93910211200012.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21000211201939 - 2³⁷ = 20862772248467 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21000211201939.

It is not a weakly prime, because it can be changed into another prime (21000211202939) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10500105600969 + 10500105600970.

It is an arithmetic number, because the mean of its divisors is an integer number (10500105600970).

Almost surely, 2^{21000211201939} is an apocalyptic number.

21000211201939 is a deficient number, since it is larger than the sum of its proper divisors (1).

21000211201939 is an equidigital number, since it uses as much as digits as its factorization.

21000211201939 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1944, while the sum is 31.

The spelling of 21000211201939 in words is "twenty-one trillion, two hundred eleven million, two hundred one thousand, nine hundred thirty-nine".