211321431421 has 4 divisors (see below), whose sum is σ = 214785717244. Its totient is φ = 207857145600.

The previous prime is 211321431367. The next prime is 211321431481. The reversal of 211321431421 is 124134123112.

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 83362125625 + 127959305796 = 288725^2 + 357714^2 .

It is a cyclic number.

It is not a de Polignac number, because 211321431421 - 2¹⁷ = 211321300349 is a prime.

It is a super-3 number, since 3×211321431421³ (a number of 35 digits) contains 333 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 (211321431481) 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, 1732142820 + ... + 1732142941.

It is an arithmetic number, because the mean of its divisors is an integer number (53696429311).

Almost surely, 2^211321431421 is an apocalyptic number.

It is an amenable number.

211321431421 is a deficient number, since it is larger than the sum of its proper divisors (3464285823).

211321431421 is an equidigital number, since it uses as much as digits as its factorization.

211321431421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3464285822.

The product of its digits is 1152, while the sum is 25.

Adding to 211321431421 its reverse (124134123112), we get a palindrome (335455554533).

The spelling of 211321431421 in words is "two hundred eleven billion, three hundred twenty-one million, four hundred thirty-one thousand, four hundred twenty-one".