21213416206441 has 4 divisors (see below), whose sum is σ = 21213524539984. Its totient is φ = 21213307872900.

The previous prime is 21213416206403. The next prime is 21213416206459. The reversal of 21213416206441 is 14460261431212.

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 21213416206441 - 2²⁷ = 21213281988713 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21213416206441.

It is not an unprimeable number, because it can be changed into a prime (21213416201441) 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, 53872515 + ... + 54264856.

It is an arithmetic number, because the mean of its divisors is an integer number (5303381134996).

Almost surely, 2^{21213416206441} is an apocalyptic number.

It is an amenable number.

21213416206441 is a deficient number, since it is larger than the sum of its proper divisors (108333543).

21213416206441 is a wasteful number, since it uses less digits than its factorization.

21213416206441 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 108333542.

The product of its (nonzero) digits is 55296, while the sum is 37.

Adding to 21213416206441 its reverse (14460261431212), we get a palindrome (35673677637653).

The spelling of 21213416206441 in words is "twenty-one trillion, two hundred thirteen billion, four hundred sixteen million, two hundred six thousand, four hundred forty-one".