82171898 has 4 divisors (see below), whose sum is σ = 123257850. Its totient is φ = 41085948.

The previous prime is 82171891. The next prime is 82171937. The reversal of 82171898 is 89817128.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 77915929 + 4255969 = 8827^2 + 2063^2 .

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (82171891) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20542973 + ... + 20542976.

Almost surely, 2^82171898 is an apocalyptic number.

82171898 is a deficient number, since it is larger than the sum of its proper divisors (41085952).

82171898 is a wasteful number, since it uses less digits than its factorization.

82171898 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41085951.

The product of its digits is 64512, while the sum is 44.

The square root of 82171898 is about 9064.8716482916. The cubic root of 82171898 is about 434.7515170471.

The spelling of 82171898 in words is "eighty-two million, one hundred seventy-one thousand, eight hundred ninety-eight".