408690993 has 16 divisors (see below), whose sum is σ = 558887616. Its totient is φ = 265493760.

The previous prime is 408690977. The next prime is 408691039. The reversal of 408690993 is 399096804.

It is a happy number.

It is not a de Polignac number, because 408690993 - 2⁴ = 408690977 is a prime.

It is not an unprimeable number, because it can be changed into a prime (408690923) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 141621 + ... + 144477.

It is an arithmetic number, because the mean of its divisors is an integer number (34930476).

Almost surely, 2^408690993 is an apocalyptic number.

It is an amenable number.

408690993 is a deficient number, since it is larger than the sum of its proper divisors (150196623).

408690993 is a wasteful number, since it uses less digits than its factorization.

408690993 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4064.

The product of its (nonzero) digits is 419904, while the sum is 48.

The square root of 408690993 is about 20216.1072662370. The cubic root of 408690993 is about 742.1044266876.

The spelling of 408690993 in words is "four hundred eight million, six hundred ninety thousand, nine hundred ninety-three".