211220121022111 has 4 divisors (see below), whose sum is σ = 214372660141912. Its totient is φ = 208067581902312.

The previous prime is 211220121022081. The next prime is 211220121022139. The reversal of 211220121022111 is 111220121022112.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 211220121022111 - 2⁷ = 211220121021983 is a prime.

It is a super-2 number, since 2×211220121022111² (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 (211220121022171) 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, 1576269559800 + ... + 1576269559933.

It is an arithmetic number, because the mean of its divisors is an integer number (53593165035478).

Almost surely, 2^{211220121022111} is an apocalyptic number.

211220121022111 is a deficient number, since it is larger than the sum of its proper divisors (3152539119801).

211220121022111 is an equidigital number, since it uses as much as digits as its factorization.

211220121022111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3152539119800.

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

Adding to 211220121022111 its reverse (111220121022112), we get a palindrome (322440242044223).

Subtracting from 211220121022111 its reverse (111220121022112), we obtain a palindrome (99999999999999).

The spelling of 211220121022111 in words is "two hundred eleven trillion, two hundred twenty billion, one hundred twenty-one million, twenty-two thousand, one hundred eleven".