21470332217 has 4 divisors (see below), whose sum is σ = 21521574480. Its totient is φ = 21419089956.

The previous prime is 21470332211. The next prime is 21470332229. The reversal of 21470332217 is 71223307412.

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 21470332217 - 2⁴ = 21470332201 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21470332211) 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, 25620503 + ... + 25621340.

It is an arithmetic number, because the mean of its divisors is an integer number (5380393620).

Almost surely, 2^21470332217 is an apocalyptic number.

It is an amenable number.

21470332217 is a deficient number, since it is larger than the sum of its proper divisors (51242263).

21470332217 is an equidigital number, since it uses as much as digits as its factorization.

21470332217 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51242262.

The product of its (nonzero) digits is 14112, while the sum is 32.

Adding to 21470332217 its reverse (71223307412), we get a palindrome (92693639629).

The spelling of 21470332217 in words is "twenty-one billion, four hundred seventy million, three hundred thirty-two thousand, two hundred seventeen".