21021305266101 has 16 divisors (see below), whose sum is σ = 32471266062464. Its totient is φ = 11847624102144.

The previous prime is 21021305266051. The next prime is 21021305266111. The reversal of 21021305266101 is 10166250312012.

It is not a de Polignac number, because 21021305266101 - 2⁹ = 21021305265589 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21021305266111) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6856262416 + ... + 6856265481.

It is an arithmetic number, because the mean of its divisors is an integer number (2029454128904).

Almost surely, 2^{21021305266101} is an apocalyptic number.

21021305266101 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

21021305266101 is a deficient number, since it is larger than the sum of its proper divisors (11449960796363).

21021305266101 is a wasteful number, since it uses less digits than its factorization.

21021305266101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13712527980.

The product of its (nonzero) digits is 4320, while the sum is 30.

Adding to 21021305266101 its reverse (10166250312012), we get a palindrome (31187555578113).

The spelling of 21021305266101 in words is "twenty-one trillion, twenty-one billion, three hundred five million, two hundred sixty-six thousand, one hundred one".