211123221031 has 4 divisors (see below), whose sum is σ = 211198598064. Its totient is φ = 211047844000.

The previous prime is 211123221019. The next prime is 211123221041. The reversal of 211123221031 is 130122321112.

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 211123221031 - 2⁵ = 211123220999 is a prime.

It is a super-2 number, since 2×211123221031² (a number of 23 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 (211123221011) 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, 37684315 + ... + 37689916.

It is an arithmetic number, because the mean of its divisors is an integer number (52799649516).

Almost surely, 2^211123221031 is an apocalyptic number.

211123221031 is a deficient number, since it is larger than the sum of its proper divisors (75377033).

211123221031 is an equidigital number, since it uses as much as digits as its factorization.

211123221031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 75377032.

The product of its (nonzero) digits is 144, while the sum is 19.

Adding to 211123221031 its reverse (130122321112), we get a palindrome (341245542143).

The spelling of 211123221031 in words is "two hundred eleven billion, one hundred twenty-three million, two hundred twenty-one thousand, thirty-one".