21235325331 has 16 divisors (see below), whose sum is σ = 30918774528. Its totient is φ = 12856965600.

The previous prime is 21235325317. The next prime is 21235325333. The reversal of 21235325331 is 13352353212.

It is a happy number.

It is not a de Polignac number, because 21235325331 - 2⁷ = 21235325203 is a prime.

It is a super-2 number, since 2×21235325331² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21235325333) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 289815 + ... + 355616.

It is an arithmetic number, because the mean of its divisors is an integer number (1932423408).

Almost surely, 2^21235325331 is an apocalyptic number.

21235325331 is a deficient number, since it is larger than the sum of its proper divisors (9683449197).

21235325331 is a wasteful number, since it uses less digits than its factorization.

21235325331 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 646442.

The product of its digits is 16200, while the sum is 30.

Adding to 21235325331 its reverse (13352353212), we get a palindrome (34587678543).

The spelling of 21235325331 in words is "twenty-one billion, two hundred thirty-five million, three hundred twenty-five thousand, three hundred thirty-one".