171782781057 has 48 divisors (see below), whose sum is σ = 264834918400. Its totient is φ = 106983957600.

The previous prime is 171782781011. The next prime is 171782781059. The reversal of 171782781057 is 750187287171.

It is a happy number.

It is not a de Polignac number, because 171782781057 - 2⁷ = 171782780929 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 171782780994 and 171782781012.

It is not an unprimeable number, because it can be changed into a prime (171782781059) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 11110182 + ... + 11125632.

Almost surely, 2^171782781057 is an apocalyptic number.

It is an amenable number.

171782781057 is a deficient number, since it is larger than the sum of its proper divisors (93052137343).

171782781057 is a wasteful number, since it uses less digits than its factorization.

171782781057 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16378 (or 16375 counting only the distinct ones).

The product of its (nonzero) digits is 1536640, while the sum is 54.

The spelling of 171782781057 in words is "one hundred seventy-one billion, seven hundred eighty-two million, seven hundred eighty-one thousand, fifty-seven".