211012121210221 has 4 divisors (see below), whose sum is σ = 211012154308444. Its totient is φ = 211012088112000.

The previous prime is 211012121210201. The next prime is 211012121210311. The reversal of 211012121210221 is 122012121210112.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 191473334337321 + 19538786872900 = 13837389^2 + 4420270^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-211012121210221 is a prime.

It is a super-2 number, since 2×211012121210221² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211012121210201) 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, 3618180 + ... + 20859421.

It is an arithmetic number, because the mean of its divisors is an integer number (52753038577111).

Almost surely, 2^{211012121210221} is an apocalyptic number.

It is an amenable number.

211012121210221 is a deficient number, since it is larger than the sum of its proper divisors (33098223).

211012121210221 is an equidigital number, since it uses as much as digits as its factorization.

211012121210221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33098222.

The product of its (nonzero) digits is 64, while the sum is 19.

Adding to 211012121210221 its reverse (122012121210112), we get a palindrome (333024242420333).

The spelling of 211012121210221 in words is "two hundred eleven trillion, twelve billion, one hundred twenty-one million, two hundred ten thousand, two hundred twenty-one".