213431481 has 12 divisors (see below), whose sum is σ = 326424852. Its totient is φ = 133917696.

The previous prime is 213431479. The next prime is 213431521. The reversal of 213431481 is 184134312.

It can be written as a sum of positive squares in 2 ways, for example, as 122877225 + 90554256 = 11085^2 + 9516^2 .

It is not a de Polignac number, because 213431481 - 2¹ = 213431479 is a prime.

It is a super-2 number, since 2×213431481² = 91105994163706722, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (213431441) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 697336 + ... + 697641.

It is an arithmetic number, because the mean of its divisors is an integer number (27202071).

Almost surely, 2^213431481 is an apocalyptic number.

It is an amenable number.

213431481 is a deficient number, since it is larger than the sum of its proper divisors (112993371).

213431481 is a wasteful number, since it uses less digits than its factorization.

213431481 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1395000 (or 1394997 counting only the distinct ones).

The product of its digits is 2304, while the sum is 27.

The square root of 213431481 is about 14609.2943361409. The cubic root of 213431481 is about 597.6122520377.

Adding to 213431481 its reverse (184134312), we get a palindrome (397565793).

The spelling of 213431481 in words is "two hundred thirteen million, four hundred thirty-one thousand, four hundred eighty-one".