21412044217 has 4 divisors (see below), whose sum is σ = 21413255760. Its totient is φ = 21410832676.

The previous prime is 21412044211. The next prime is 21412044239. The reversal of 21412044217 is 71244021412.

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 21412044217 - 2³ = 21412044209 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21412044211) 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, 578863 + ... + 614740.

It is an arithmetic number, because the mean of its divisors is an integer number (5353313940).

Almost surely, 2^21412044217 is an apocalyptic number.

It is an amenable number.

21412044217 is a deficient number, since it is larger than the sum of its proper divisors (1211543).

21412044217 is a wasteful number, since it uses less digits than its factorization.

21412044217 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1211542.

The product of its (nonzero) digits is 3584, while the sum is 28.

Adding to 21412044217 its reverse (71244021412), we get a palindrome (92656065629).

The spelling of 21412044217 in words is "twenty-one billion, four hundred twelve million, forty-four thousand, two hundred seventeen".