808205121 has 28 divisors (see below), whose sum is σ = 1229913552. Its totient is φ = 530729496.

The previous prime is 808205117. The next prime is 808205137. The reversal of 808205121 is 121502808.

It is not a de Polignac number, because 808205121 - 2² = 808205117 is a prime.

It is a super-2 number, since 2×808205121² = 1306391035221249282, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (808205821) by changing a digit.

It is a polite number, since it can be written in 27 ways as a sum of consecutive naturals, for example, 40570 + ... + 57116.

It is an arithmetic number, because the mean of its divisors is an integer number (43925484).

Almost surely, 2^808205121 is an apocalyptic number.

808205121 is a gapful number since it is divisible by the number (81) formed by its first and last digit.

It is an amenable number.

808205121 is a deficient number, since it is larger than the sum of its proper divisors (421708431).

808205121 is an equidigital number, since it uses as much as digits as its factorization.

808205121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16632 (or 16617 counting only the distinct ones).

The product of its (nonzero) digits is 1280, while the sum is 27.

The square root of 808205121 is about 28428.9486439439. The cubic root of 808205121 is about 931.4807109357.

Adding to 808205121 its reverse (121502808), we get a palindrome (929707929).

The spelling of 808205121 in words is "eight hundred eight million, two hundred five thousand, one hundred twenty-one".