499961681 has 2 divisors, whose sum is σ = 499961682. Its totient is φ = 499961680.

The previous prime is 499961669. The next prime is 499961699. The reversal of 499961681 is 186169994.

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., 252969025 + 246992656 = 15905^2 + 15716^2 .

It is a cyclic number.

It is not a de Polignac number, because 499961681 - 2⁶ = 499961617 is a prime.

It is a super-2 number, since 2×499961681² = 499923364936691522, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (499961621) 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 as a sum of consecutive naturals, namely, 249980840 + 249980841.

It is an arithmetic number, because the mean of its divisors is an integer number (249980841).

Almost surely, 2^499961681 is an apocalyptic number.

It is an amenable number.

499961681 is a deficient number, since it is larger than the sum of its proper divisors (1).

499961681 is an equidigital number, since it uses as much as digits as its factorization.

499961681 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 839808, while the sum is 53.

The square root of 499961681 is about 22359.8229196924. The cubic root of 499961681 is about 793.6802495925.

The spelling of 499961681 in words is "four hundred ninety-nine million, nine hundred sixty-one thousand, six hundred eighty-one".