399029945 has 4 divisors (see below), whose sum is σ = 478835940. Its totient is φ = 319223952.

The previous prime is 399029929. The next prime is 399029947. The reversal of 399029945 is 549920993.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 80478841 + 318551104 = 8971^2 + 17848^2 .

It is a cyclic number.

It is not a de Polignac number, because 399029945 - 2⁴ = 399029929 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 399029893 and 399029902.

It is not an unprimeable number, because it can be changed into a prime (399029947) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 39902990 + ... + 39902999.

It is an arithmetic number, because the mean of its divisors is an integer number (119708985).

Almost surely, 2^399029945 is an apocalyptic number.

It is an amenable number.

399029945 is a deficient number, since it is larger than the sum of its proper divisors (79805995).

399029945 is an equidigital number, since it uses as much as digits as its factorization.

399029945 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 79805994.

The product of its (nonzero) digits is 787320, while the sum is 50.

The square root of 399029945 is about 19975.7339039145. The cubic root of 399029945 is about 736.2101987299.

The spelling of 399029945 in words is "three hundred ninety-nine million, twenty-nine thousand, nine hundred forty-five".