491582881 has 2 divisors, whose sum is σ = 491582882. Its totient is φ = 491582880.

The previous prime is 491582879. The next prime is 491582891. The reversal of 491582881 is 188285194.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 397803025 + 93779856 = 19945^2 + 9684^2 .

It is a cyclic number.

It is not a de Polignac number, because 491582881 - 2¹ = 491582879 is a prime.

It is a super-2 number, since 2×491582881² = 483307457784520322, which contains 22 as substring.

Together with 491582879, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (491582831) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 245791440 + 245791441.

It is an arithmetic number, because the mean of its divisors is an integer number (245791441).

Almost surely, 2^491582881 is an apocalyptic number.

It is an amenable number.

491582881 is a deficient number, since it is larger than the sum of its proper divisors (1).

491582881 is an equidigital number, since it uses as much as digits as its factorization.

491582881 is an evil number, because the sum of its binary digits is even.

The product of its digits is 184320, while the sum is 46.

The square root of 491582881 is about 22171.6684306797. The cubic root of 491582881 is about 789.2215164048.

The spelling of 491582881 in words is "four hundred ninety-one million, five hundred eighty-two thousand, eight hundred eighty-one".