1239023945 has 4 divisors (see below), whose sum is σ = 1486828740. Its totient is φ = 991219152.

The previous prime is 1239023897. The next prime is 1239023957. The reversal of 1239023945 is 5493209321.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5493209321 = 9929 ⋅553249.

It can be written as a sum of positive squares in 2 ways, for example, as 777461689 + 461562256 = 27883^2 + 21484^2 .

It is a cyclic number.

It is not a de Polignac number, because 1239023945 - 2¹⁸ = 1238761801 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1239023899 and 1239023908.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 123902390 + ... + 123902399.

It is an arithmetic number, because the mean of its divisors is an integer number (371707185).

Almost surely, 2^1239023945 is an apocalyptic number.

It is an amenable number.

1239023945 is a deficient number, since it is larger than the sum of its proper divisors (247804795).

1239023945 is an equidigital number, since it uses as much as digits as its factorization.

1239023945 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 247804794.

The product of its (nonzero) digits is 58320, while the sum is 38.

The square root of 1239023945 is about 35199.7719452840. The cubic root of 1239023945 is about 1074.0551120305.

The spelling of 1239023945 in words is "one billion, two hundred thirty-nine million, twenty-three thousand, nine hundred forty-five".