21221353412050 has 36 divisors (see below), whose sum is σ = 43386267839418. Its totient is φ = 7716855784000.

The previous prime is 21221353412011. The next prime is 21221353412071. The reversal of 21221353412050 is 5021435312212.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 16813944431361 + 4407408980689 = 4100481^2 + 2099383^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 1753824811 + ... + 1753836910.

Almost surely, 2^{21221353412050} is an apocalyptic number.

21221353412050 is an abundant number, since it is smaller than the sum of its proper divisors (22164914427368).

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

21221353412050 is a wasteful number, since it uses less digits than its factorization.

21221353412050 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3507661755 (or 3507661739 counting only the distinct ones).

The product of its (nonzero) digits is 14400, while the sum is 31.

Adding to 21221353412050 its reverse (5021435312212), we get a palindrome (26242788724262).

The spelling of 21221353412050 in words is "twenty-one trillion, two hundred twenty-one billion, three hundred fifty-three million, four hundred twelve thousand, fifty".