21012200003421 has 48 divisors (see below), whose sum is σ = 33249000545280. Its totient is φ = 12681357939360.

The previous prime is 21012200003339. The next prime is 21012200003437. The reversal of 21012200003421 is 12430000221012.

It is a happy number.

21012200003421 is a `hidden beast` number, since 2 + 101 + 220 + 0 + 0 + 0 + 342 + 1 = 666.

It is not a de Polignac number, because 21012200003421 - 2¹⁸ = 21012199741277 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21012200003394 and 21012200003403.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21012200003471) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 24392070 + ... + 25238808.

It is an arithmetic number, because the mean of its divisors is an integer number (692687511360).

Almost surely, 2^{21012200003421} is an apocalyptic number.

It is an amenable number.

21012200003421 is a deficient number, since it is larger than the sum of its proper divisors (12236800541859).

21012200003421 is a wasteful number, since it uses less digits than its factorization.

21012200003421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 847806 (or 847803 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

Adding to 21012200003421 its reverse (12430000221012), we get a palindrome (33442200224433).

The spelling of 21012200003421 in words is "twenty-one trillion, twelve billion, two hundred million, three thousand, four hundred twenty-one".