21051000050 has 12 divisors (see below), whose sum is σ = 39154860186. Its totient is φ = 8420400000.

The previous prime is 21051000029. The next prime is 21051000059. The reversal of 21051000050 is 5000015012.

It can be written as a sum of positive squares in 3 ways, for example, as 18036221401 + 3014778649 = 134299^2 + 54907^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21050999989 and 21051000034.

It is not an unprimeable number, because it can be changed into a prime (21051000059) 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 5 ways as a sum of consecutive naturals, for example, 210509951 + ... + 210510050.

Almost surely, 2^21051000050 is an apocalyptic number.

21051000050 is a deficient number, since it is larger than the sum of its proper divisors (18103860136).

21051000050 is a wasteful number, since it uses less digits than its factorization.

21051000050 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 421020013 (or 421020008 counting only the distinct ones).

The product of its (nonzero) digits is 50, while the sum is 14.

Adding to 21051000050 its reverse (5000015012), we get a palindrome (26051015062).

The spelling of 21051000050 in words is "twenty-one billion, fifty-one million, fifty", and thus it is an aban number and an uban number.