211212110021 has 16 divisors (see below), whose sum is σ = 235726339968. Its totient is φ = 187631270400.

The previous prime is 211212109993. The next prime is 211212110029. The reversal of 211212110021 is 120011212112.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-211212110021 is a prime.

It is a super-2 number, since 2×211212110021² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 211212109978 and 211212110005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211212110029) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1108376 + ... + 1284881.

It is an arithmetic number, because the mean of its divisors is an integer number (14732896248).

Almost surely, 2^211212110021 is an apocalyptic number.

It is an amenable number.

211212110021 is a deficient number, since it is larger than the sum of its proper divisors (24514229947).

211212110021 is a wasteful number, since it uses less digits than its factorization.

211212110021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2393452.

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 211212110021 its reverse (120011212112), we get a palindrome (331223322133).

The spelling of 211212110021 in words is "two hundred eleven billion, two hundred twelve million, one hundred ten thousand, twenty-one".