408086821 has 4 divisors (see below), whose sum is σ = 421250944. Its totient is φ = 394922700.

The previous prime is 408086797. The next prime is 408086827. The reversal of 408086821 is 128680804.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 408086821 - 2²⁷ = 273869093 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (408086827) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6582015 + ... + 6582076.

It is an arithmetic number, because the mean of its divisors is an integer number (105312736).

Almost surely, 2^408086821 is an apocalyptic number.

It is an amenable number.

408086821 is a deficient number, since it is larger than the sum of its proper divisors (13164123).

408086821 is a wasteful number, since it uses less digits than its factorization.

408086821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13164122.

The product of its (nonzero) digits is 24576, while the sum is 37.

The square root of 408086821 is about 20201.1589023996. The cubic root of 408086821 is about 741.7385595306.

The spelling of 408086821 in words is "four hundred eight million, eighty-six thousand, eight hundred twenty-one".