21101101009 has 2 divisors, whose sum is σ = 21101101010.
Its totient is φ = 21101101008.
The previous prime is 21101100989. The next prime is 21101101027. The reversal of 21101101009 is 90010110112.
It is a strong prime.
It can be written as a sum of positive squares in only one way, i.e., 21096691009 + 4410000 = 145247^2 + 2100^2
It is a cyclic number.
It is not a de Polignac number, because 21101101009 - 221 = 21099003857 is a prime.
It is a junction number, because it is equal to n+sod(n) for n = 21101100983 and 21101101001.
It is not a weakly prime, because it can be changed into another prime (21101107009) by changing a digit.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10550550504 + 10550550505.
It is an arithmetic number, because the mean of its divisors is an integer number (10550550505).
Almost surely, 221101101009 is an apocalyptic number.
It is an amenable number.
21101101009 is a deficient number, since it is larger than the sum of its proper divisors (1).
21101101009 is an equidigital number, since it uses as much as digits as its factorization.
21101101009 is an odious number, because the sum of its binary digits is odd.
The product of its (nonzero) digits is 18, while the sum is 16.
The spelling of 21101101009 in words is "twenty-one billion, one hundred one million, one hundred one thousand, nine".