491997357 has 72 divisors (see below), whose sum is σ = 796539744. Its totient is φ = 292271616.

The previous prime is 491997353. The next prime is 491997409. The reversal of 491997357 is 753799194.

It is a happy number.

It is not a de Polignac number, because 491997357 - 2² = 491997353 is a prime.

It is a super-2 number, since 2×491997357² = 484122798589970898, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (491997353) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 5927638 + ... + 5927720.

It is an arithmetic number, because the mean of its divisors is an integer number (11063052).

Almost surely, 2^491997357 is an apocalyptic number.

It is an amenable number.

491997357 is a deficient number, since it is larger than the sum of its proper divisors (304542387).

491997357 is a wasteful number, since it uses less digits than its factorization.

491997357 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 219 (or 199 counting only the distinct ones).

The product of its digits is 2143260, while the sum is 54.

The square root of 491997357 is about 22181.0134349177. The cubic root of 491997357 is about 789.4432636748.

The spelling of 491997357 in words is "four hundred ninety-one million, nine hundred ninety-seven thousand, three hundred fifty-seven".