145667521 has 4 divisors (see below), whose sum is σ = 145893312. Its totient is φ = 145441732.

The previous prime is 145667503. The next prime is 145667563. The reversal of 145667521 is 125766541.

It is a happy number.

145667521 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, 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 145667521 - 2⁹ = 145667009 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (145667321) 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, 111925 + ... + 113218.

It is an arithmetic number, because the mean of its divisors is an integer number (36473328).

Almost surely, 2^145667521 is an apocalyptic number.

It is an amenable number.

145667521 is a deficient number, since it is larger than the sum of its proper divisors (225791).

145667521 is an equidigital number, since it uses as much as digits as its factorization.

145667521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 225790.

The product of its digits is 50400, while the sum is 37.

The square root of 145667521 is about 12069.2800530935. The cubic root of 145667521 is about 526.1637326596.

The spelling of 145667521 in words is "one hundred forty-five million, six hundred sixty-seven thousand, five hundred twenty-one".