211304540621 has 4 divisors (see below), whose sum is σ = 211306201500. Its totient is φ = 211302879744.

The previous prime is 211304540561. The next prime is 211304540633. The reversal of 211304540621 is 126045403112.

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

It can be written as a sum of positive squares in 2 ways, for example, as 156273949225 + 55030591396 = 395315^2 + 234586^2 .

It is a cyclic number.

It is not a de Polignac number, because 211304540621 - 2¹⁰ = 211304539597 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211304540921) 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, 622196 + ... + 899853.

It is an arithmetic number, because the mean of its divisors is an integer number (52826550375).

Almost surely, 2^211304540621 is an apocalyptic number.

It is an amenable number.

211304540621 is a deficient number, since it is larger than the sum of its proper divisors (1660879).

211304540621 is a wasteful number, since it uses less digits than its factorization.

211304540621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1660878.

The product of its (nonzero) digits is 5760, while the sum is 29.

Adding to 211304540621 its reverse (126045403112), we get a palindrome (337349943733).

The spelling of 211304540621 in words is "two hundred eleven billion, three hundred four million, five hundred forty thousand, six hundred twenty-one".