210101112121 has 4 divisors (see below), whose sum is σ = 210102038244. Its totient is φ = 210100186000.

The previous prime is 210101112041. The next prime is 210101112197. The reversal of 210101112121 is 121211101012.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 142155391225 + 67945720896 = 377035^2 + 260664^2 .

It is a cyclic number.

It is not a de Polignac number, because 210101112121 - 2⁷ = 210101111993 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (210101119121) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 132891 + ... + 661711.

It is an arithmetic number, because the mean of its divisors is an integer number (52525509561).

Almost surely, 2^210101112121 is an apocalyptic number.

It is an amenable number.

210101112121 is a deficient number, since it is larger than the sum of its proper divisors (926123).

210101112121 is an equidigital number, since it uses as much as digits as its factorization.

210101112121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 926122.

The product of its (nonzero) digits is 8, while the sum is 13.

Adding to 210101112121 its reverse (121211101012), we get a palindrome (331312213133).

The spelling of 210101112121 in words is "two hundred ten billion, one hundred one million, one hundred twelve thousand, one hundred twenty-one".