21221313221310 has 128 divisors (see below), whose sum is σ = 55679494348800. Its totient is φ = 5153136783360.

The previous prime is 21221313221299. The next prime is 21221313221351. The reversal of 21221313221310 is 1312231312212.

It is a super-2 number, since 2×21221313221310² (a number of 27 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 63 ways as a sum of consecutive naturals, for example, 69554071 + ... + 69858509.

It is an arithmetic number, because the mean of its divisors is an integer number (434996049600).

Almost surely, 2^{21221313221310} is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21221313221310, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27839747174400).

21221313221310 is an abundant number, since it is smaller than the sum of its proper divisors (34458181127490).

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

21221313221310 is a wasteful number, since it uses less digits than its factorization.

21221313221310 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 308906.

The product of its (nonzero) digits is 864, while the sum is 24.

Adding to 21221313221310 its reverse (1312231312212), we get a palindrome (22533544533522).

The spelling of 21221313221310 in words is "twenty-one trillion, two hundred twenty-one billion, three hundred thirteen million, two hundred twenty-one thousand, three hundred ten".