208836840130821 has 32 divisors (see below), whose sum is σ = 353637662188800. Its totient is φ = 119317963446720.

The previous prime is 208836840130811. The next prime is 208836840130859. The reversal of 208836840130821 is 128031048638802.

208836840130821 is a `hidden beast` number, since 20 + 8 + 83 + 68 + 401 + 3 + 0 + 82 + 1 = 666.

It is not a de Polignac number, because 208836840130821 - 2¹⁴ = 208836840114437 is a prime.

It is a super-2 number, since 2×208836840130821² (a number of 29 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (208836840130811) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 79132450 + ... + 81728931.

It is an arithmetic number, because the mean of its divisors is an integer number (11051176943400).

Almost surely, 2^{208836840130821} is an apocalyptic number.

208836840130821 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

208836840130821 is a deficient number, since it is larger than the sum of its proper divisors (144800822057979).

208836840130821 is a wasteful number, since it uses less digits than its factorization.

208836840130821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 160868266 (or 160868260 counting only the distinct ones).

The product of its (nonzero) digits is 3538944, while the sum is 54.

The spelling of 208836840130821 in words is "two hundred eight trillion, eight hundred thirty-six billion, eight hundred forty million, one hundred thirty thousand, eight hundred twenty-one".