208951919561 has 12 divisors (see below), whose sum is σ = 265163475600. Its totient is φ = 162819677160.

The previous prime is 208951919537. The next prime is 208951919573. The reversal of 208951919561 is 165919159802.

It is not a de Polignac number, because 208951919561 - 2²⁶ = 208884810697 is a prime.

It is a super-2 number, since 2×208951919561² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 208951919497 and 208951919506.

It is not an unprimeable number, because it can be changed into a prime (208951910561) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 193832411 + ... + 193833488.

It is an arithmetic number, because the mean of its divisors is an integer number (22096956300).

Almost surely, 2^208951919561 is an apocalyptic number.

It is an amenable number.

208951919561 is a deficient number, since it is larger than the sum of its proper divisors (56211556039).

208951919561 is a wasteful number, since it uses less digits than its factorization.

208951919561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 387665924 (or 387665917 counting only the distinct ones).

The product of its (nonzero) digits is 1749600, while the sum is 56.

The spelling of 208951919561 in words is "two hundred eight billion, nine hundred fifty-one million, nine hundred nineteen thousand, five hundred sixty-one".