145532021 has 2 divisors, whose sum is σ = 145532022. Its totient is φ = 145532020.

The previous prime is 145532003. The next prime is 145532041. The reversal of 145532021 is 120235541.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 78127921 + 67404100 = 8839^2 + 8210^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-145532021 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (145532041) 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 as a sum of consecutive naturals, namely, 72766010 + 72766011.

It is an arithmetic number, because the mean of its divisors is an integer number (72766011).

Almost surely, 2^145532021 is an apocalyptic number.

It is an amenable number.

145532021 is a deficient number, since it is larger than the sum of its proper divisors (1).

145532021 is an equidigital number, since it uses as much as digits as its factorization.

145532021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1200, while the sum is 23.

The square root of 145532021 is about 12063.6653219492. The cubic root of 145532021 is about 526.0005361259. Note that the first 3 decimals are identical.

Adding to 145532021 its reverse (120235541), we get a palindrome (265767562).

The spelling of 145532021 in words is "one hundred forty-five million, five hundred thirty-two thousand, twenty-one".