145305257 has 4 divisors (see below), whose sum is σ = 145378560. Its totient is φ = 145231956.

The previous prime is 145305241. The next prime is 145305269. The reversal of 145305257 is 752503541.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 145305257 - 2⁴ = 145305241 is a prime.

It is a super-2 number, since 2×145305257² = 42227235423672098, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (145305857) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 33593 + ... + 37670.

It is an arithmetic number, because the mean of its divisors is an integer number (36344640).

Almost surely, 2^145305257 is an apocalyptic number.

It is an amenable number.

145305257 is a deficient number, since it is larger than the sum of its proper divisors (73303).

145305257 is an equidigital number, since it uses as much as digits as its factorization.

145305257 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 73302.

The product of its (nonzero) digits is 21000, while the sum is 32.

The square root of 145305257 is about 12054.2630218525. The cubic root of 145305257 is about 525.7271942402.

Adding to 145305257 its reverse (752503541), we get a palindrome (897808798).

The spelling of 145305257 in words is "one hundred forty-five million, three hundred five thousand, two hundred fifty-seven".