212133135521 has 4 divisors (see below), whose sum is σ = 212188657044. Its totient is φ = 212077614000.

The previous prime is 212133135463. The next prime is 212133135569. The reversal of 212133135521 is 125531331212.

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 80295156496 + 131837979025 = 283364^2 + 363095^2 .

It is a cyclic number.

It is not a de Polignac number, because 212133135521 - 2²² = 212128941217 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (212133135821) 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, 27755030 + ... + 27762671.

It is an arithmetic number, because the mean of its divisors is an integer number (53047164261).

Almost surely, 2^212133135521 is an apocalyptic number.

It is an amenable number.

212133135521 is a deficient number, since it is larger than the sum of its proper divisors (55521523).

212133135521 is an equidigital number, since it uses as much as digits as its factorization.

212133135521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55521522.

The product of its digits is 5400, while the sum is 29.

Adding to 212133135521 its reverse (125531331212), we get a palindrome (337664466733).

The spelling of 212133135521 in words is "two hundred twelve billion, one hundred thirty-three million, one hundred thirty-five thousand, five hundred twenty-one".