21001101100247 has 2 divisors, whose sum is σ = 21001101100248. Its totient is φ = 21001101100246.

The previous prime is 21001101100183. The next prime is 21001101100253. The reversal of 21001101100247 is 74200110110012.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21001101100247 - 2⁶ = 21001101100183 is a prime.

It is a super-2 number, since 2×21001101100247² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21001101103247) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10500550550123 + 10500550550124.

It is an arithmetic number, because the mean of its divisors is an integer number (10500550550124).

Almost surely, 2^{21001101100247} is an apocalyptic number.

21001101100247 is a deficient number, since it is larger than the sum of its proper divisors (1).

21001101100247 is an equidigital number, since it uses as much as digits as its factorization.

21001101100247 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 112, while the sum is 20.

Adding to 21001101100247 its reverse (74200110110012), we get a palindrome (95201211210259).

The spelling of 21001101100247 in words is "twenty-one trillion, one billion, one hundred one million, one hundred thousand, two hundred forty-seven".