21335031523 has 8 divisors (see below), whose sum is σ = 22984326288. Its totient is φ = 19686899424.

The previous prime is 21335031517. The next prime is 21335031539. The reversal of 21335031523 is 32513053312.

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 21335031523 - 2⁵ = 21335031491 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21335031491 and 21335031500.

It is not an unprimeable number, because it can be changed into a prime (21335031583) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 252361 + ... + 326122.

It is an arithmetic number, because the mean of its divisors is an integer number (2873040786).

Almost surely, 2^21335031523 is an apocalyptic number.

21335031523 is a deficient number, since it is larger than the sum of its proper divisors (1649294765).

21335031523 is a wasteful number, since it uses less digits than its factorization.

21335031523 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 581333.

The product of its (nonzero) digits is 8100, while the sum is 28.

Adding to 21335031523 its reverse (32513053312), we get a palindrome (53848084835).

The spelling of 21335031523 in words is "twenty-one billion, three hundred thirty-five million, thirty-one thousand, five hundred twenty-three".