208978681236 has 36 divisors (see below), whose sum is σ = 528011229312. Its totient is φ = 64301132064.

The previous prime is 208978681207. The next prime is 208978681243. The reversal of 208978681236 is 632186879802.

It is a super-2 number, since 2×208978681236² (a number of 23 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 208978681236.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 51521316 + ... + 51525371.

It is an arithmetic number, because the mean of its divisors is an integer number (14666978592).

Almost surely, 2^208978681236 is an apocalyptic number.

208978681236 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

208978681236 is an abundant number, since it is smaller than the sum of its proper divisors (319032548076).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

208978681236 is a wasteful number, since it uses less digits than its factorization.

208978681236 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 103046720 (or 103046705 counting only the distinct ones).

The product of its (nonzero) digits is 13934592, while the sum is 60.

The spelling of 208978681236 in words is "two hundred eight billion, nine hundred seventy-eight million, six hundred eighty-one thousand, two hundred thirty-six".