21121322503616 has 112 divisors (see below), whose sum is σ = 42727541875200. Its totient is φ = 10357248964608.

The previous prime is 21121322503601. The next prime is 21121322503627. The reversal of 21121322503616 is 61630522312112.

It is a super-2 number, since 2×21121322503616² (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 15 ways as a sum of consecutive naturals, for example, 847995035 + ... + 848019941.

It is an arithmetic number, because the mean of its divisors is an integer number (381495909600).

Almost surely, 2^{21121322503616} 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 21121322503616, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21363770937600).

21121322503616 is an abundant number, since it is smaller than the sum of its proper divisors (21606219371584).

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

21121322503616 is a wasteful number, since it uses less digits than its factorization.

21121322503616 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26114 (or 26104 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 35.

Adding to 21121322503616 its reverse (61630522312112), we get a palindrome (82751844815728).

The spelling of 21121322503616 in words is "twenty-one trillion, one hundred twenty-one billion, three hundred twenty-two million, five hundred three thousand, six hundred sixteen".