145477221 has 4 divisors (see below), whose sum is σ = 193969632. Its totient is φ = 96984812.

The previous prime is 145477201. The next prime is 145477237. The reversal of 145477221 is 122774541.

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 145477221 - 2¹⁰ = 145476197 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (145477201) 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, 24246201 + ... + 24246206.

It is an arithmetic number, because the mean of its divisors is an integer number (48492408).

Almost surely, 2^145477221 is an apocalyptic number.

It is an amenable number.

145477221 is a deficient number, since it is larger than the sum of its proper divisors (48492411).

145477221 is an equidigital number, since it uses as much as digits as its factorization.

145477221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48492410.

The product of its digits is 15680, while the sum is 33.

The square root of 145477221 is about 12061.3938249275. The cubic root of 145477221 is about 525.9345061028.

The spelling of 145477221 in words is "one hundred forty-five million, four hundred seventy-seven thousand, two hundred twenty-one".