491620171875 has 112 divisors (see below), whose sum is σ = 941237952000. Its totient is φ = 223581600000.

The previous prime is 491620171873. The next prime is 491620171957. The reversal of 491620171875 is 578171026194.

It is not a de Polignac number, because 491620171875 - 2¹ = 491620171873 is a prime.

It is not an unprimeable number, because it can be changed into a prime (491620171871) by changing a digit.

It is a polite number, since it can be written in 111 ways as a sum of consecutive naturals, for example, 65293111 + ... + 65300639.

Almost surely, 2^491620171875 is an apocalyptic number.

491620171875 is a deficient number, since it is larger than the sum of its proper divisors (449617780125).

491620171875 is an frugal number, since it uses more digits than its factorization.

491620171875 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7768 (or 7743 counting only the distinct ones).

The product of its (nonzero) digits is 846720, while the sum is 51.

The spelling of 491620171875 in words is "four hundred ninety-one billion, six hundred twenty million, one hundred seventy-one thousand, eight hundred seventy-five".