399604491 has 48 divisors (see below), whose sum is σ = 694747872. Its totient is φ = 218073600.

The previous prime is 399604487. The next prime is 399604493. The reversal of 399604491 is 194406993.

399604491 is a `hidden beast` number, since 39 + 9 + 604 + 4 + 9 + 1 = 666.

It is not a de Polignac number, because 399604491 - 2² = 399604487 is a prime.

It is not an unprimeable number, because it can be changed into a prime (399604493) 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 47 ways as a sum of consecutive naturals, for example, 48981 + ... + 56553.

It is an arithmetic number, because the mean of its divisors is an integer number (14473914).

Almost surely, 2^399604491 is an apocalyptic number.

399604491 is a deficient number, since it is larger than the sum of its proper divisors (295143381).

399604491 is a wasteful number, since it uses less digits than its factorization.

399604491 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7644 (or 7641 counting only the distinct ones).

The product of its (nonzero) digits is 209952, while the sum is 45.

The square root of 399604491 is about 19990.1098296132. The cubic root of 399604491 is about 736.5633750424.

The spelling of 399604491 in words is "three hundred ninety-nine million, six hundred four thousand, four hundred ninety-one".