209132779968 has 84 divisors (see below), whose sum is σ = 685075846000. Its totient is φ = 59752221696.

The previous prime is 209132779939. The next prime is 209132779993. The reversal of 209132779968 is 869977231902.

209132779968 is a `hidden beast` number, since 209 + 13 + 277 + 99 + 68 = 666.

It is a tau number, because it is divible by the number of its divisors (84).

It is a Harshad number since it is a multiple of its sum of digits (63).

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, 25930093 + ... + 25938156.

Almost surely, 2^209132779968 is an apocalyptic number.

209132779968 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

209132779968 is an abundant number, since it is smaller than the sum of its proper divisors (475943066032).

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

209132779968 is a wasteful number, since it uses less digits than its factorization.

209132779968 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51868274 (or 51868261 counting only the distinct ones).

The product of its (nonzero) digits is 20575296, while the sum is 63.

The spelling of 209132779968 in words is "two hundred nine billion, one hundred thirty-two million, seven hundred seventy-nine thousand, nine hundred sixty-eight".