21081314251050 has 96 divisors (see below), whose sum is σ = 52929133568640. Its totient is φ = 5552206387200.

The previous prime is 21081314251043. The next prime is 21081314251087. The reversal of 21081314251050 is 5015241318012.

It is a super-2 number, since 2×21081314251050² (a number of 27 digits) contains 22 as substring.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 10865139 + ... + 12657561.

It is an arithmetic number, because the mean of its divisors is an integer number (551345141340).

Almost surely, 2^{21081314251050} is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21081314251050, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26464566784320).

21081314251050 is an abundant number, since it is smaller than the sum of its proper divisors (31847819317590).

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

21081314251050 is a wasteful number, since it uses less digits than its factorization.

21081314251050 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1793408 (or 1793403 counting only the distinct ones).

The product of its (nonzero) digits is 9600, while the sum is 33.

Adding to 21081314251050 its reverse (5015241318012), we get a palindrome (26096555569062).

The spelling of 21081314251050 in words is "twenty-one trillion, eighty-one billion, three hundred fourteen million, two hundred fifty-one thousand, fifty".