399661015 has 8 divisors (see below), whose sum is σ = 516485088. Its totient is φ = 295134240.

The previous prime is 399660979. The next prime is 399661027. The reversal of 399661015 is 510166993.

399661015 is digitally balanced in base 6, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 399661015 - 2¹⁷ = 399529943 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3074251 + ... + 3074380.

It is an arithmetic number, because the mean of its divisors is an integer number (64560636).

Almost surely, 2^399661015 is an apocalyptic number.

399661015 is a deficient number, since it is larger than the sum of its proper divisors (116824073).

399661015 is a wasteful number, since it uses less digits than its factorization.

399661015 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6148649.

The product of its (nonzero) digits is 43740, while the sum is 40.

The square root of 399661015 is about 19991.5235787571. The cubic root of 399661015 is about 736.5981023342.

The spelling of 399661015 in words is "three hundred ninety-nine million, six hundred sixty-one thousand, fifteen".