210001012221 has 128 divisors (see below), whose sum is σ = 394331406336. Its totient is φ = 95891143680.

The previous prime is 210001012213. The next prime is 210001012307. The reversal of 210001012221 is 122210100012.

210001012221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 210001012221 - 2³ = 210001012213 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 210001012197 and 210001012206.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (210001012421) 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 127 ways as a sum of consecutive naturals, for example, 5202111 + ... + 5242323.

It is an arithmetic number, because the mean of its divisors is an integer number (3080714112).

Almost surely, 2^210001012221 is an apocalyptic number.

210001012221 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

210001012221 is a deficient number, since it is larger than the sum of its proper divisors (184330394115).

210001012221 is a wasteful number, since it uses less digits than its factorization.

210001012221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40331.

The product of its (nonzero) digits is 16, while the sum is 12.

Adding to 210001012221 its reverse (122210100012), we get a palindrome (332211112233).

The spelling of 210001012221 in words is "two hundred ten billion, one million, twelve thousand, two hundred twenty-one".