145246781 has 4 divisors (see below), whose sum is σ = 145276092. Its totient is φ = 145217472.

The previous prime is 145246757. The next prime is 145246847. The reversal of 145246781 is 187642541.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 187642541 = 8287 ⋅22643.

It can be written as a sum of positive squares in 2 ways, for example, as 99900025 + 45346756 = 9995^2 + 6734^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-145246781 is a prime.

It is a super-2 number, since 2×145246781² = 42193254781723922, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (145246741) 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, 5180 + ... + 17813.

It is an arithmetic number, because the mean of its divisors is an integer number (36319023).

Almost surely, 2^145246781 is an apocalyptic number.

It is an amenable number.

145246781 is a deficient number, since it is larger than the sum of its proper divisors (29311).

145246781 is an equidigital number, since it uses as much as digits as its factorization.

145246781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29310.

The product of its digits is 53760, while the sum is 38.

The square root of 145246781 is about 12051.8372458310. The cubic root of 145246781 is about 525.6566610081.

The spelling of 145246781 in words is "one hundred forty-five million, two hundred forty-six thousand, seven hundred eighty-one".