491789017 has 4 divisors (see below), whose sum is σ = 492698596. Its totient is φ = 490879440.

The previous prime is 491789009. The next prime is 491789021. The reversal of 491789017 is 710987194.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 710987194 = 2 ⋅355493597.

It can be written as a sum of positive squares in 2 ways, for example, as 211527936 + 280261081 = 14544^2 + 16741^2 .

It is a cyclic number.

It is not a de Polignac number, because 491789017 - 2³ = 491789009 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (491789057) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 453978 + ... + 455059.

It is an arithmetic number, because the mean of its divisors is an integer number (123174649).

Almost surely, 2^491789017 is an apocalyptic number.

It is an amenable number.

491789017 is a deficient number, since it is larger than the sum of its proper divisors (909579).

491789017 is an equidigital number, since it uses as much as digits as its factorization.

491789017 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 909578.

The product of its (nonzero) digits is 127008, while the sum is 46.

The square root of 491789017 is about 22176.3165787288. The cubic root of 491789017 is about 789.3318160364.

The spelling of 491789017 in words is "four hundred ninety-one million, seven hundred eighty-nine thousand, seventeen".