145920281 has 4 divisors (see below), whose sum is σ = 157144932. Its totient is φ = 134695632.

The previous prime is 145920259. The next prime is 145920283. The reversal of 145920281 is 182029541.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 182029541 = 83 ⋅2193127.

It can be written as a sum of positive squares in 2 ways, for example, as 97199881 + 48720400 = 9859^2 + 6980^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-145920281 is a prime.

It is a super-2 number, since 2×145920281² = 42585456814237922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (145920283) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5612306 + ... + 5612331.

It is an arithmetic number, because the mean of its divisors is an integer number (39286233).

Almost surely, 2^145920281 is an apocalyptic number.

It is an amenable number.

145920281 is a deficient number, since it is larger than the sum of its proper divisors (11224651).

145920281 is a wasteful number, since it uses less digits than its factorization.

145920281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11224650.

The product of its (nonzero) digits is 5760, while the sum is 32.

The square root of 145920281 is about 12079.7467274774. The cubic root of 145920281 is about 526.4678871608.

It can be divided in two parts, 14 and 5920281, that added together give a palindrome (5920295).

The spelling of 145920281 in words is "one hundred forty-five million, nine hundred twenty thousand, two hundred eighty-one".