491495381 has 16 divisors (see below), whose sum is σ = 562318848. Its totient is φ = 425568000.

The previous prime is 491495357. The next prime is 491495437. The reversal of 491495381 is 183594194.

It is a de Polignac number, because none of the positive numbers 2^k-491495381 is a prime.

It is a super-2 number, since 2×491495381² = 483135419088670322, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (491495321) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 65156 + ... + 72306.

It is an arithmetic number, because the mean of its divisors is an integer number (35144928).

Almost surely, 2^491495381 is an apocalyptic number.

It is an amenable number.

491495381 is a deficient number, since it is larger than the sum of its proper divisors (70823467).

491495381 is a wasteful number, since it uses less digits than its factorization.

491495381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7492.

The product of its digits is 155520, while the sum is 44.

The square root of 491495381 is about 22169.6951039025. The cubic root of 491495381 is about 789.1746874210.

The spelling of 491495381 in words is "four hundred ninety-one million, four hundred ninety-five thousand, three hundred eighty-one".