21335110521 has 8 divisors (see below), whose sum is σ = 28740080544. Its totient is φ = 14076773760.

The previous prime is 21335110513. The next prime is 21335110529. The reversal of 21335110521 is 12501153312.

It is an interprime number because it is at equal distance from previous prime (21335110513) and next prime (21335110529).

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

It is not a de Polignac number, because 21335110521 - 2³ = 21335110513 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21335110491 and 21335110500.

It is not an unprimeable number, because it can be changed into a prime (21335110529) 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, 36657975 + ... + 36658556.

It is an arithmetic number, because the mean of its divisors is an integer number (3592510068).

Almost surely, 2^21335110521 is an apocalyptic number.

It is an amenable number.

21335110521 is a deficient number, since it is larger than the sum of its proper divisors (7404970023).

21335110521 is an equidigital number, since it uses as much as digits as its factorization.

21335110521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 73316631.

The product of its (nonzero) digits is 900, while the sum is 24.

Adding to 21335110521 its reverse (12501153312), we get a palindrome (33836263833).

The spelling of 21335110521 in words is "twenty-one billion, three hundred thirty-five million, one hundred ten thousand, five hundred twenty-one".