21020115012011 has 2 divisors, whose sum is σ = 21020115012012. Its totient is φ = 21020115012010.

The previous prime is 21020115011911. The next prime is 21020115012049. The reversal of 21020115012011 is 11021051102012.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21020115012011 - 2²² = 21020110817707 is a prime.

It is not a weakly prime, because it can be changed into another prime (21020115012511) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10510057506005 + 10510057506006.

It is an arithmetic number, because the mean of its divisors is an integer number (10510057506006).

Almost surely, 2^{21020115012011} is an apocalyptic number.

21020115012011 is a deficient number, since it is larger than the sum of its proper divisors (1).

21020115012011 is an equidigital number, since it uses as much as digits as its factorization.

21020115012011 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 40, while the sum is 17.

Adding to 21020115012011 its reverse (11021051102012), we get a palindrome (32041166114023).

The spelling of 21020115012011 in words is "twenty-one trillion, twenty billion, one hundred fifteen million, twelve thousand, eleven".