145057221 has 12 divisors (see below), whose sum is σ = 214638060. Its totient is φ = 94345920.

The previous prime is 145057219. The next prime is 145057247. The reversal of 145057221 is 122750541.

It can be written as a sum of positive squares in 2 ways, for example, as 60233121 + 84824100 = 7761^2 + 9210^2 .

It is not a de Polignac number, because 145057221 - 2¹ = 145057219 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (145057261) 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 11 ways as a sum of consecutive naturals, for example, 196186 + ... + 196923.

It is an arithmetic number, because the mean of its divisors is an integer number (17886505).

Almost surely, 2^145057221 is an apocalyptic number.

It is an amenable number.

145057221 is a deficient number, since it is larger than the sum of its proper divisors (69580839).

145057221 is a wasteful number, since it uses less digits than its factorization.

145057221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 393156 (or 393153 counting only the distinct ones).

The product of its (nonzero) digits is 2800, while the sum is 27.

The square root of 145057221 is about 12043.9703171338. The cubic root of 145057221 is about 525.4278851841.

The spelling of 145057221 in words is "one hundred forty-five million, fifty-seven thousand, two hundred twenty-one".