213231145 has 4 divisors (see below), whose sum is σ = 255877380. Its totient is φ = 170584912.

The previous prime is 213231131. The next prime is 213231157. The reversal of 213231145 is 541132312.

It is a happy number.

213231145 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 can be written as a sum of positive squares in 2 ways, for example, as 168662169 + 44568976 = 12987^2 + 6676^2 .

It is a cyclic number.

It is not a de Polignac number, because 213231145 - 2¹³ = 213222953 is a prime.

It is a super-2 number, since 2×213231145² = 90935042396022050, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21323110 + ... + 21323119.

It is an arithmetic number, because the mean of its divisors is an integer number (63969345).

Almost surely, 2^213231145 is an apocalyptic number.

It is an amenable number.

213231145 is a deficient number, since it is larger than the sum of its proper divisors (42646235).

213231145 is an equidigital number, since it uses as much as digits as its factorization.

213231145 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42646234.

The product of its digits is 720, while the sum is 22.

The square root of 213231145 is about 14602.4362693353. The cubic root of 213231145 is about 597.4252119531.

Adding to 213231145 its reverse (541132312), we get a palindrome (754363457).

The spelling of 213231145 in words is "two hundred thirteen million, two hundred thirty-one thousand, one hundred forty-five".