145231213 has 4 divisors (see below), whose sum is σ = 146728540. Its totient is φ = 143733888.

The previous prime is 145231211. The next prime is 145231241. The reversal of 145231213 is 312132541.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 312132541 = 7 ⋅44590363.

It can be written as a sum of positive squares in 2 ways, for example, as 39100009 + 106131204 = 6253^2 + 10302^2 .

It is a cyclic number.

It is not a de Polignac number, because 145231213 - 2¹ = 145231211 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (145231211) 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, 748518 + ... + 748711.

It is an arithmetic number, because the mean of its divisors is an integer number (36682135).

Almost surely, 2^145231213 is an apocalyptic number.

It is an amenable number.

145231213 is a deficient number, since it is larger than the sum of its proper divisors (1497327).

145231213 is an equidigital number, since it uses as much as digits as its factorization.

145231213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1497326.

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

The square root of 145231213 is about 12051.1913518955. The cubic root of 145231213 is about 525.6378798339.

Adding to 145231213 its reverse (312132541), we get a palindrome (457363754).

The spelling of 145231213 in words is "one hundred forty-five million, two hundred thirty-one thousand, two hundred thirteen".