211021213021021 has 8 divisors (see below), whose sum is σ = 235089945541080. Its totient is φ = 188071956432192.

The previous prime is 211021213020979. The next prime is 211021213021049. The reversal of 211021213021021 is 120120312120112.

It can be written as a sum of positive squares in 4 ways, for example, as 10540703756025 + 200480509264996 = 3246645^2 + 14159114^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 211021213021021 - 2⁹ = 211021213020509 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 211021213021021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211021213021061) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 279868982410 + ... + 279868983163.

It is an arithmetic number, because the mean of its divisors is an integer number (29386243192635).

Almost surely, 2^{211021213021021} is an apocalyptic number.

It is an amenable number.

211021213021021 is a deficient number, since it is larger than the sum of its proper divisors (24068732520059).

211021213021021 is a wasteful number, since it uses less digits than its factorization.

211021213021021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 559737965615.

The product of its (nonzero) digits is 96, while the sum is 19.

Adding to 211021213021021 its reverse (120120312120112), we get a palindrome (331141525141133).

Subtracting from 211021213021021 its reverse (120120312120112), we obtain a palindrome (90900900900909).

The spelling of 211021213021021 in words is "two hundred eleven trillion, twenty-one billion, two hundred thirteen million, twenty-one thousand, twenty-one".