21072601042217 has 4 divisors (see below), whose sum is σ = 21095732328576. Its totient is φ = 21049469755860.

The previous prime is 21072601042169. The next prime is 21072601042237. The reversal of 21072601042217 is 71224010627012.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21072601042217 - 2¹² = 21072601038121 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21072601042237) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11565641813 + ... + 11565643634.

It is an arithmetic number, because the mean of its divisors is an integer number (5273933082144).

Almost surely, 2^{21072601042217} is an apocalyptic number.

It is an amenable number.

21072601042217 is a deficient number, since it is larger than the sum of its proper divisors (23131286359).

21072601042217 is an equidigital number, since it uses as much as digits as its factorization.

21072601042217 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23131286358.

The product of its (nonzero) digits is 18816, while the sum is 35.

Adding to 21072601042217 its reverse (71224010627012), we get a palindrome (92296611669229).

The spelling of 21072601042217 in words is "twenty-one trillion, seventy-two billion, six hundred one million, forty-two thousand, two hundred seventeen".