21001001109983 has 2 divisors, whose sum is σ = 21001001109984. Its totient is φ = 21001001109982.

The previous prime is 21001001109953. The next prime is 21001001110073. The reversal of 21001001109983 is 38990110010012.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21001001109983 - 2²⁴ = 21000984332767 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21001001109923) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10500500554991 + 10500500554992.

It is an arithmetic number, because the mean of its divisors is an integer number (10500500554992).

Almost surely, 2^{21001001109983} is an apocalyptic number.

21001001109983 is a deficient number, since it is larger than the sum of its proper divisors (1).

21001001109983 is an equidigital number, since it uses as much as digits as its factorization.

21001001109983 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3888, while the sum is 35.

Adding to 21001001109983 its reverse (38990110010012), we get a palindrome (59991111119995).

The spelling of 21001001109983 in words is "twenty-one trillion, one billion, one million, one hundred nine thousand, nine hundred eighty-three".