491509031 has 4 divisors (see below), whose sum is σ = 529317432. Its totient is φ = 453700632.

The previous prime is 491509001. The next prime is 491509069. The reversal of 491509031 is 130905194.

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

It is a cyclic number.

It is not a de Polignac number, because 491509031 - 2¹⁴ = 491492647 is a prime.

It is a super-2 number, since 2×491509031² = 483162255109117922, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (491509001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 18904181 + ... + 18904206.

It is an arithmetic number, because the mean of its divisors is an integer number (132329358).

Almost surely, 2^491509031 is an apocalyptic number.

491509031 is a deficient number, since it is larger than the sum of its proper divisors (37808401).

491509031 is a wasteful number, since it uses less digits than its factorization.

491509031 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37808400.

The product of its (nonzero) digits is 4860, while the sum is 32.

The square root of 491509031 is about 22170.0029544427. The cubic root of 491509031 is about 789.1819931083.

The spelling of 491509031 in words is "four hundred ninety-one million, five hundred nine thousand, thirty-one".