213445561 has 8 divisors (see below), whose sum is σ = 246306944. Its totient is φ = 181176480.

The previous prime is 213445559. The next prime is 213445577. The reversal of 213445561 is 165544312.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 213445561 - 2¹ = 213445559 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (213445501) 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 7 ways as a sum of consecutive naturals, for example, 147300 + ... + 148741.

It is an arithmetic number, because the mean of its divisors is an integer number (30788368).

Almost surely, 2^213445561 is an apocalyptic number.

It is an amenable number.

213445561 is a deficient number, since it is larger than the sum of its proper divisors (32861383).

213445561 is a wasteful number, since it uses less digits than its factorization.

213445561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 296151.

The product of its digits is 14400, while the sum is 31.

The square root of 213445561 is about 14609.7762132074. The cubic root of 213445561 is about 597.6253931724.

Adding to 213445561 its reverse (165544312), we get a palindrome (378989873).

The spelling of 213445561 in words is "two hundred thirteen million, four hundred forty-five thousand, five hundred sixty-one".