21213560443 has 4 divisors (see below), whose sum is σ = 21380596480. Its totient is φ = 21046524408.

The previous prime is 21213560387. The next prime is 21213560471. The reversal of 21213560443 is 34406531212.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21213560443 - 2⁹ = 21213559931 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21213500443) 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, 83517828 + ... + 83518081.

It is an arithmetic number, because the mean of its divisors is an integer number (5345149120).

Almost surely, 2^21213560443 is an apocalyptic number.

21213560443 is a deficient number, since it is larger than the sum of its proper divisors (167036037).

21213560443 is a wasteful number, since it uses less digits than its factorization.

21213560443 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 167036036.

The product of its (nonzero) digits is 17280, while the sum is 31.

The spelling of 21213560443 in words is "twenty-one billion, two hundred thirteen million, five hundred sixty thousand, four hundred forty-three".