213540431 has 16 divisors (see below), whose sum is σ = 243817728. Its totient is φ = 185587200.

The previous prime is 213540419. The next prime is 213540463. The reversal of 213540431 is 134045312.

It is a cyclic number.

It is not a de Polignac number, because 213540431 - 2⁶ = 213540367 is a prime.

It is a super-2 number, since 2×213540431² = 91199031343331522, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 213540397 and 213540406.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (213540401) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7751 + ... + 22071.

It is an arithmetic number, because the mean of its divisors is an integer number (15238608).

Almost surely, 2^213540431 is an apocalyptic number.

213540431 is a deficient number, since it is larger than the sum of its proper divisors (30277297).

213540431 is a wasteful number, since it uses less digits than its factorization.

213540431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14402.

The product of its (nonzero) digits is 1440, while the sum is 23.

The square root of 213540431 is about 14613.0226510466. The cubic root of 213540431 is about 597.7139221051.

Adding to 213540431 its reverse (134045312), we get a palindrome (347585743).

The spelling of 213540431 in words is "two hundred thirteen million, five hundred forty thousand, four hundred thirty-one".