491231421 has 24 divisors (see below), whose sum is σ = 718434080. Its totient is φ = 323416800.

The previous prime is 491231413. The next prime is 491231431. The reversal of 491231421 is 124132194.

It is a happy number.

491231421 is a `hidden beast` number, since 4 + 9 + 1 + 231 + 421 = 666.

It is not a de Polignac number, because 491231421 - 2³ = 491231413 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (491231431) 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 23 ways as a sum of consecutive naturals, for example, 263031 + ... + 264891.

Almost surely, 2^491231421 is an apocalyptic number.

It is an amenable number.

491231421 is a deficient number, since it is larger than the sum of its proper divisors (227202659).

491231421 is a wasteful number, since it uses less digits than its factorization.

491231421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2217 (or 2214 counting only the distinct ones).

The product of its digits is 1728, while the sum is 27.

The square root of 491231421 is about 22163.7411327601. The cubic root of 491231421 is about 789.0333854128.

The spelling of 491231421 in words is "four hundred ninety-one million, two hundred thirty-one thousand, four hundred twenty-one".