21243311310 has 64 divisors (see below), whose sum is σ = 55011700800. Its totient is φ = 5219036160.

The previous prime is 21243311303. The next prime is 21243311321. The reversal of 21243311310 is 1311334212.

It is a super-2 number, since 2×21243311310² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 150916 + ... + 255464.

It is an arithmetic number, because the mean of its divisors is an integer number (859557825).

Almost surely, 2^21243311310 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21243311310, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27505850400).

21243311310 is an abundant number, since it is smaller than the sum of its proper divisors (33768389490).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21243311310 is a wasteful number, since it uses less digits than its factorization.

21243311310 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 105093.

The product of its (nonzero) digits is 432, while the sum is 21.

Adding to 21243311310 its reverse (1311334212), we get a palindrome (22554645522).

The spelling of 21243311310 in words is "twenty-one billion, two hundred forty-three million, three hundred eleven thousand, three hundred ten".