211210110021 has 4 divisors (see below), whose sum is σ = 281613480032. Its totient is φ = 140806740012.

The previous prime is 211210110017. The next prime is 211210110053. The reversal of 211210110021 is 120011012112.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 211210110021 - 2² = 211210110017 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 211210109979 and 211210110006.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211210110011) 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, 35201685001 + ... + 35201685006.

It is an arithmetic number, because the mean of its divisors is an integer number (70403370008).

Almost surely, 2^211210110021 is an apocalyptic number.

It is an amenable number.

211210110021 is a deficient number, since it is larger than the sum of its proper divisors (70403370011).

211210110021 is an equidigital number, since it uses as much as digits as its factorization.

211210110021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 70403370010.

The product of its (nonzero) digits is 8, while the sum is 12.

Adding to 211210110021 its reverse (120011012112), we get a palindrome (331221122133).

The spelling of 211210110021 in words is "two hundred eleven billion, two hundred ten million, one hundred ten thousand, twenty-one".