145123731 has 24 divisors (see below), whose sum is σ = 223276144. Its totient is φ = 94128480.

The previous prime is 145123709. The next prime is 145123763. The reversal of 145123731 is 137321541.

It is not a de Polignac number, because 145123731 - 2²² = 140929427 is a prime.

It is a super-5 number, since 5×145123731⁵ (a number of 42 digits) contains 55555 as substring. Note that it is a super-d number also for d = 2.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 145123695 and 145123704.

It is not an unprimeable number, because it can be changed into a prime (145123631) 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 23 ways as a sum of consecutive naturals, for example, 921 + ... + 17061.

Almost surely, 2^145123731 is an apocalyptic number.

145123731 is a deficient number, since it is larger than the sum of its proper divisors (78152413).

145123731 is an equidigital number, since it uses as much as digits as its factorization.

145123731 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16193 (or 16181 counting only the distinct ones).

The product of its digits is 2520, while the sum is 27.

The square root of 145123731 is about 12046.7311333822. The cubic root of 145123731 is about 525.5081773353.

The spelling of 145123731 in words is "one hundred forty-five million, one hundred twenty-three thousand, seven hundred thirty-one".