211363221643 has 4 divisors (see below), whose sum is σ = 241557967600. Its totient is φ = 181168475688.

The previous prime is 211363221541. The next prime is 211363221683. The reversal of 211363221643 is 346122363112.

It is a happy number.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-211363221643 is a prime.

It is a super-2 number, since 2×211363221643² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 211363221599 and 211363221608.

It is not an unprimeable number, because it can be changed into a prime (211363221683) 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, 15097372968 + ... + 15097372981.

It is an arithmetic number, because the mean of its divisors is an integer number (60389491900).

Almost surely, 2^211363221643 is an apocalyptic number.

211363221643 is a deficient number, since it is larger than the sum of its proper divisors (30194745957).

211363221643 is an equidigital number, since it uses as much as digits as its factorization.

211363221643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30194745956.

The product of its digits is 31104, while the sum is 34.

Adding to 211363221643 its reverse (346122363112), we get a palindrome (557485584755).

The spelling of 211363221643 in words is "two hundred eleven billion, three hundred sixty-three million, two hundred twenty-one thousand, six hundred forty-three".