211423021 has 4 divisors (see below), whose sum is σ = 218713500. Its totient is φ = 204132544.

The previous prime is 211422979. The next prime is 211423063. The reversal of 211423021 is 120324112.

211423021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is an interprime number because it is at equal distance from previous prime (211422979) and next prime (211423063).

It can be written as a sum of positive squares in 2 ways, for example, as 156500100 + 54922921 = 12510^2 + 7411^2 .

It is a cyclic number.

It is not a de Polignac number, because 211423021 - 2¹³ = 211414829 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 211422986 and 211423004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211423081) 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, 3645196 + ... + 3645253.

It is an arithmetic number, because the mean of its divisors is an integer number (54678375).

Almost surely, 2^211423021 is an apocalyptic number.

It is an amenable number.

211423021 is a deficient number, since it is larger than the sum of its proper divisors (7290479).

211423021 is an equidigital number, since it uses as much as digits as its factorization.

211423021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7290478.

The product of its (nonzero) digits is 96, while the sum is 16.

The square root of 211423021 is about 14540.3927388499. The cubic root of 211423021 is about 595.7317654358.

Adding to 211423021 its reverse (120324112), we get a palindrome (331747133).

The spelling of 211423021 in words is "two hundred eleven million, four hundred twenty-three thousand, twenty-one".