21101021243105 has 8 divisors (see below), whose sum is σ = 25798984463592. Its totient is φ = 16562311013248.

The previous prime is 21101021243023. The next prime is 21101021243153. The reversal of 21101021243105 is 50134212010112.

It can be written as a sum of positive squares in 4 ways, for example, as 3115143810529 + 17985877432576 = 1764977^2 + 4240976^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21101021243105 - 2²² = 21101017048801 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 39813247364 + ... + 39813247893.

It is an arithmetic number, because the mean of its divisors is an integer number (3224873057949).

Almost surely, 2^{21101021243105} is an apocalyptic number.

It is an amenable number.

21101021243105 is a deficient number, since it is larger than the sum of its proper divisors (4697963220487).

21101021243105 is an equidigital number, since it uses as much as digits as its factorization.

21101021243105 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 79626495315.

The product of its (nonzero) digits is 480, while the sum is 23.

Adding to 21101021243105 its reverse (50134212010112), we get a palindrome (71235233253217).

The spelling of 21101021243105 in words is "twenty-one trillion, one hundred one billion, twenty-one million, two hundred forty-three thousand, one hundred five".