21221211012201 has 24 divisors (see below), whose sum is σ = 31481598485064. Its totient is φ = 13764986346240.

The previous prime is 21221211012139. The next prime is 21221211012203. The reversal of 21221211012201 is 10221011212212.

21221211012201 is a `hidden beast` number, since 21 + 221 + 211 + 0 + 12 + 201 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 2738958800400 + 18482252211801 = 1654980^2 + 4299099^2 .

It is not a de Polignac number, because 21221211012201 - 2¹³ = 21221211004009 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21221211012203) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 50311741 + ... + 50731781.

It is an arithmetic number, because the mean of its divisors is an integer number (1311733270211).

Almost surely, 2^{21221211012201} is an apocalyptic number.

It is an amenable number.

21221211012201 is a deficient number, since it is larger than the sum of its proper divisors (10260387472863).

21221211012201 is a wasteful number, since it uses less digits than its factorization.

21221211012201 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 571801 (or 571798 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 18.

Adding to 21221211012201 its reverse (10221011212212), we get a palindrome (31442222224413).

The spelling of 21221211012201 in words is "twenty-one trillion, two hundred twenty-one billion, two hundred eleven million, twelve thousand, two hundred one".