494121681 has 16 divisors (see below), whose sum is σ = 740260800. Its totient is φ = 325711584.

The previous prime is 494121647. The next prime is 494121721. The reversal of 494121681 is 186121494.

494121681 is a `hidden beast` number, since 494 + 1 + 2 + 168 + 1 = 666.

It is not a de Polignac number, because 494121681 - 2¹³ = 494113489 is a prime.

It is a super-2 number, since 2×494121681² = 488312471268531522, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (494121601) 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 15 ways as a sum of consecutive naturals, for example, 100411 + ... + 105216.

It is an arithmetic number, because the mean of its divisors is an integer number (46266300).

Almost surely, 2^494121681 is an apocalyptic number.

It is an amenable number.

494121681 is a deficient number, since it is larger than the sum of its proper divisors (246139119).

494121681 is a wasteful number, since it uses less digits than its factorization.

494121681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 205725 (or 205719 counting only the distinct ones).

The product of its digits is 13824, while the sum is 36.

The square root of 494121681 is about 22228.8479458563. The cubic root of 494121681 is about 790.5778398050.

The spelling of 494121681 in words is "four hundred ninety-four million, one hundred twenty-one thousand, six hundred eighty-one".