145373521 has 2 divisors, whose sum is σ = 145373522. Its totient is φ = 145373520.

The previous prime is 145373467. The next prime is 145373537. The reversal of 145373521 is 125373541.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 131423296 + 13950225 = 11464^2 + 3735^2 .

It is an emirp because it is prime and its reverse (125373541) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 145373521 - 2¹⁵ = 145340753 is a prime.

It is a super-2 number, since 2×145373521² = 42266921215874882, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (145373561) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 72686760 + 72686761.

It is an arithmetic number, because the mean of its divisors is an integer number (72686761).

Almost surely, 2^145373521 is an apocalyptic number.

It is an amenable number.

145373521 is a deficient number, since it is larger than the sum of its proper divisors (1).

145373521 is an equidigital number, since it uses as much as digits as its factorization.

145373521 is an evil number, because the sum of its binary digits is even.

The product of its digits is 12600, while the sum is 31.

The square root of 145373521 is about 12057.0942187577. The cubic root of 145373521 is about 525.8095097355.

The spelling of 145373521 in words is "one hundred forty-five million, three hundred seventy-three thousand, five hundred twenty-one".