145012561 has 4 divisors (see below), whose sum is σ = 146295972. Its totient is φ = 143729152.

The previous prime is 145012523. The next prime is 145012597. The reversal of 145012561 is 165210541.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 165210541 = 23 ⋅7183067.

It can be written as a sum of positive squares in 2 ways, for example, as 40564161 + 104448400 = 6369^2 + 10220^2 .

It is a cyclic number.

It is not a de Polignac number, because 145012561 - 2¹¹ = 145010513 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (145012961) 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 3 ways as a sum of consecutive naturals, for example, 641536 + ... + 641761.

It is an arithmetic number, because the mean of its divisors is an integer number (36573993).

Almost surely, 2^145012561 is an apocalyptic number.

It is an amenable number.

145012561 is a deficient number, since it is larger than the sum of its proper divisors (1283411).

145012561 is a wasteful number, since it uses less digits than its factorization.

145012561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1283410.

The product of its (nonzero) digits is 1200, while the sum is 25.

The square root of 145012561 is about 12042.1161346335. The cubic root of 145012561 is about 525.3739569991.

The spelling of 145012561 in words is "one hundred forty-five million, twelve thousand, five hundred sixty-one".