145563221 has 2 divisors, whose sum is σ = 145563222. Its totient is φ = 145563220.

The previous prime is 145563211. The next prime is 145563233. The reversal of 145563221 is 122365541.

145563221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 121660900 + 23902321 = 11030^2 + 4889^2 .

It is a cyclic number.

It is not a de Polignac number, because 145563221 - 2¹⁸ = 145301077 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (145563211) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 72781610 + 72781611.

It is an arithmetic number, because the mean of its divisors is an integer number (72781611).

Almost surely, 2^145563221 is an apocalyptic number.

It is an amenable number.

145563221 is a deficient number, since it is larger than the sum of its proper divisors (1).

145563221 is an equidigital number, since it uses as much as digits as its factorization.

145563221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7200, while the sum is 29.

The square root of 145563221 is about 12064.9583919714. The cubic root of 145563221 is about 526.0381224568.

The spelling of 145563221 in words is "one hundred forty-five million, five hundred sixty-three thousand, two hundred twenty-one".