21021122121201 has 8 divisors (see below), whose sum is σ = 31142403142560. Its totient is φ = 14014081414116.

The previous prime is 21021122121173. The next prime is 21021122121269. The reversal of 21021122121201 is 10212122112012.

21021122121201 is a `hidden beast` number, since 2 + 10 + 211 + 221 + 21 + 201 = 666.

It is not a de Polignac number, because 21021122121201 - 2⁵ = 21021122121169 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21021122122201) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 389280039255 + ... + 389280039308.

It is an arithmetic number, because the mean of its divisors is an integer number (3892800392820).

Almost surely, 2^{21021122121201} is an apocalyptic number.

It is an amenable number.

21021122121201 is a deficient number, since it is larger than the sum of its proper divisors (10121281021359).

21021122121201 is an equidigital number, since it uses as much as digits as its factorization.

21021122121201 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 778560078572 (or 778560078566 counting only the distinct ones).

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

Adding to 21021122121201 its reverse (10212122112012), we get a palindrome (31233244233213).

The spelling of 21021122121201 in words is "twenty-one trillion, twenty-one billion, one hundred twenty-two million, one hundred twenty-one thousand, two hundred one".