209771068977 has 16 divisors (see below), whose sum is σ = 313848908160. Its totient is φ = 138462750000.

The previous prime is 209771068939. The next prime is 209771069021. The reversal of 209771068977 is 779860177902.

It is not a de Polignac number, because 209771068977 - 2³⁴ = 192591199793 is a prime.

It is not an unprimeable number, because it can be changed into a prime (209771068877) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 38459149 + ... + 38464602.

It is an arithmetic number, because the mean of its divisors is an integer number (19615556760).

Almost surely, 2^209771068977 is an apocalyptic number.

209771068977 is a gapful number since it is divisible by the number (27) formed by its first and last digit.

It is an amenable number.

209771068977 is a deficient number, since it is larger than the sum of its proper divisors (104077839183).

209771068977 is a wasteful number, since it uses less digits than its factorization.

209771068977 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 76923861 (or 76923855 counting only the distinct ones).

The product of its (nonzero) digits is 18670176, while the sum is 63.

The spelling of 209771068977 in words is "two hundred nine billion, seven hundred seventy-one million, sixty-eight thousand, nine hundred seventy-seven".