171649878797 has 2 divisors, whose sum is σ = 171649878798. Its totient is φ = 171649878796.

The previous prime is 171649878791. The next prime is 171649878811. The reversal of 171649878797 is 797878946171.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 169306737961 + 2343140836 = 411469^2 + 48406^2 .

It is a cyclic number.

It is not a de Polignac number, because 171649878797 - 2²⁴ = 171633101581 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (171649878791) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 85824939398 + 85824939399.

It is an arithmetic number, because the mean of its divisors is an integer number (85824939399).

Almost surely, 2^171649878797 is an apocalyptic number.

It is an amenable number.

171649878797 is a deficient number, since it is larger than the sum of its proper divisors (1).

171649878797 is an equidigital number, since it uses as much as digits as its factorization.

171649878797 is an evil number, because the sum of its binary digits is even.

The product of its digits is 298722816, while the sum is 74.

The spelling of 171649878797 in words is "one hundred seventy-one billion, six hundred forty-nine million, eight hundred seventy-eight thousand, seven hundred ninety-seven".