21353324631 has 8 divisors (see below), whose sum is σ = 29452861680. Its totient is φ = 13744668672.

The previous prime is 21353324617. The next prime is 21353324639. The reversal of 21353324631 is 13642335312.

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

It is not a de Polignac number, because 21353324631 - 2¹⁵ = 21353291863 is a prime.

It is a super-2 number, since 2×21353324631² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21353324592 and 21353324601.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21353324639) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 122720170 + ... + 122720343.

It is an arithmetic number, because the mean of its divisors is an integer number (3681607710).

Almost surely, 2^21353324631 is an apocalyptic number.

21353324631 is a deficient number, since it is larger than the sum of its proper divisors (8099537049).

21353324631 is a wasteful number, since it uses less digits than its factorization.

21353324631 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 245440545.

The product of its digits is 38880, while the sum is 33.

Adding to 21353324631 its reverse (13642335312), we get a palindrome (34995659943).

The spelling of 21353324631 in words is "twenty-one billion, three hundred fifty-three million, three hundred twenty-four thousand, six hundred thirty-one".