145547981 has 2 divisors, whose sum is σ = 145547982. Its totient is φ = 145547980.

The previous prime is 145547977. The next prime is 145548023. The reversal of 145547981 is 189745541.

145547981 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 129185956 + 16362025 = 11366^2 + 4045^2 .

It is a cyclic number.

It is not a de Polignac number, because 145547981 - 2² = 145547977 is a prime.

It is a super-2 number, since 2×145547981² = 42368429546352722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (145547951) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 72773990 + 72773991.

It is an arithmetic number, because the mean of its divisors is an integer number (72773991).

Almost surely, 2^145547981 is an apocalyptic number.

It is an amenable number.

145547981 is a deficient number, since it is larger than the sum of its proper divisors (1).

145547981 is an equidigital number, since it uses as much as digits as its factorization.

145547981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 201600, while the sum is 44.

The square root of 145547981 is about 12064.3267943139. The cubic root of 145547981 is about 526.0197636509.

The spelling of 145547981 in words is "one hundred forty-five million, five hundred forty-seven thousand, nine hundred eighty-one".