209959429968 has 140 divisors (see below), whose sum is σ = 645793580628. Its totient is φ = 65869562880.

The previous prime is 209959429961. The next prime is 209959429969. The reversal of 209959429968 is 869924959902.

209959429968 is a `hidden beast` number, since 2 + 0 + 9 + 9 + 594 + 29 + 9 + 6 + 8 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 70241961024 + 139717468944 = 265032^2 + 373788^2 .

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a junction number, because it is equal to n+sod(n) for n = 209959429896 and 209959429905.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (209959429961) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 27 ways as a sum of consecutive naturals, for example, 331143 + ... + 727718.

Almost surely, 2^209959429968 is an apocalyptic number.

It is an amenable number.

209959429968 is an abundant number, since it is smaller than the sum of its proper divisors (435834150660).

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

209959429968 is a wasteful number, since it uses less digits than its factorization.

209959429968 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1058904 (or 1058883 counting only the distinct ones).

The product of its (nonzero) digits is 226748160, while the sum is 72.

The spelling of 209959429968 in words is "two hundred nine billion, nine hundred fifty-nine million, four hundred twenty-nine thousand, nine hundred sixty-eight".