145531241021 has 2 divisors, whose sum is σ = 145531241022. Its totient is φ = 145531241020.

The previous prime is 145531241017. The next prime is 145531241071. The reversal of 145531241021 is 120142135541.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 145095475396 + 435765625 = 380914^2 + 20875^2 .

It is a cyclic number.

It is not a de Polignac number, because 145531241021 - 2² = 145531241017 is a prime.

It is a super-2 number, since 2×145531241021² (a number of 23 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (145531241071) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 72765620510 + 72765620511.

It is an arithmetic number, because the mean of its divisors is an integer number (72765620511).

Almost surely, 2^145531241021 is an apocalyptic number.

It is an amenable number.

145531241021 is a deficient number, since it is larger than the sum of its proper divisors (1).

145531241021 is an equidigital number, since it uses as much as digits as its factorization.

145531241021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4800, while the sum is 29.

Adding to 145531241021 its reverse (120142135541), we get a palindrome (265673376562).

The spelling of 145531241021 in words is "one hundred forty-five billion, five hundred thirty-one million, two hundred forty-one thousand, twenty-one".