408216999 has 4 divisors (see below), whose sum is σ = 544289336. Its totient is φ = 272144664.

The previous prime is 408216973. The next prime is 408217097. The reversal of 408216999 is 999612804.

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

It is not a de Polignac number, because 408216999 - 2⁷ = 408216871 is a prime.

It is a super-2 number, since 2×408216999² = 333282236545132002, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (408216199) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 68036164 + ... + 68036169.

It is an arithmetic number, because the mean of its divisors is an integer number (136072334).

Almost surely, 2^408216999 is an apocalyptic number.

408216999 is a deficient number, since it is larger than the sum of its proper divisors (136072337).

408216999 is a wasteful number, since it uses less digits than its factorization.

408216999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 136072336.

The product of its (nonzero) digits is 279936, while the sum is 48.

The square root of 408216999 is about 20204.3806883557. The cubic root of 408216999 is about 741.8174216517.

The spelling of 408216999 in words is "four hundred eight million, two hundred sixteen thousand, nine hundred ninety-nine".