213451 has 4 divisors (see below), whose sum is σ = 243952. Its totient is φ = 182952.

The previous prime is 213449. The next prime is 213461. The reversal of 213451 is 154312.

213451 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 not a de Polignac number, because 213451 - 2¹ = 213449 is a prime.

It is a super-3 number, since 3×213451³ = 29175333965918553, which contains 333 as substring. Note that it is a super-d number also for d = 2.

It is an Ulam number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (213461) 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, 15240 + ... + 15253.

It is an arithmetic number, because the mean of its divisors is an integer number (60988).

2²¹³⁴⁵¹ is an apocalyptic number.

213451 is a deficient number, since it is larger than the sum of its proper divisors (30501).

213451 is an equidigital number, since it uses as much as digits as its factorization.

213451 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30500.

The product of its digits is 120, while the sum is 16.

The square root of 213451 is about 462.0075756955. The cubic root of 213451 is about 59.7630469341.

Adding to 213451 its reverse (154312), we get a palindrome (367763).

The spelling of 213451 in words is "two hundred thirteen thousand, four hundred fifty-one".