21313113012 has 72 divisors (see below), whose sum is σ = 55914698112. Its totient is φ = 7098710400.

The previous prime is 21313113011. The next prime is 21313113037. The reversal of 21313113012 is 21031131312.

21313113012 is a `hidden beast` number, since 21 + 31 + 311 + 301 + 2 = 666.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21313113011) 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 23 ways as a sum of consecutive naturals, for example, 1314837 + ... + 1330947.

Almost surely, 2^21313113012 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21313113012, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27957349056).

21313113012 is an abundant number, since it is smaller than the sum of its proper divisors (34601585100).

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

21313113012 is a wasteful number, since it uses less digits than its factorization.

21313113012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17491 (or 17477 counting only the distinct ones).

The product of its (nonzero) digits is 108, while the sum is 18.

Adding to 21313113012 its reverse (21031131312), we get a palindrome (42344244324).

The spelling of 21313113012 in words is "twenty-one billion, three hundred thirteen million, one hundred thirteen thousand, twelve".