145444681 has 4 divisors (see below), whose sum is σ = 145637572. Its totient is φ = 145251792.

The previous prime is 145444631. The next prime is 145444687. The reversal of 145444681 is 186444541.

145444681 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 186444541 = 487 ⋅382843.

It can be written as a sum of positive squares in 2 ways, for example, as 126225225 + 19219456 = 11235^2 + 4384^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-145444681 is a prime.

It is a super-2 number, since 2×145444681² = 42308310462383522, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 145444681.

It is not an unprimeable number, because it can be changed into a prime (145444687) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 95310 + ... + 96823.

It is an arithmetic number, because the mean of its divisors is an integer number (36409393).

Almost surely, 2^145444681 is an apocalyptic number.

It is an amenable number.

145444681 is a deficient number, since it is larger than the sum of its proper divisors (192891).

145444681 is an equidigital number, since it uses as much as digits as its factorization.

145444681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 192890.

The product of its digits is 61440, while the sum is 37.

The square root of 145444681 is about 12060.0448174955. The cubic root of 145444681 is about 525.8952899175.

The spelling of 145444681 in words is "one hundred forty-five million, four hundred forty-four thousand, six hundred eighty-one".