994585981 has 2 divisors, whose sum is σ = 994585982. Its totient is φ = 994585980.

The previous prime is 994585979. The next prime is 994585993. The reversal of 994585981 is 189585499.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 992817081 + 1768900 = 31509^2 + 1330^2 .

It is a cyclic number.

It is not a de Polignac number, because 994585981 - 2¹ = 994585979 is a prime.

It is a super-2 number, since 2×994585981² = 1978402547203464722, which contains 22 as substring.

Together with 994585979, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (994585931) 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, 497292990 + 497292991.

It is an arithmetic number, because the mean of its divisors is an integer number (497292991).

Almost surely, 2^994585981 is an apocalyptic number.

It is an amenable number.

994585981 is a deficient number, since it is larger than the sum of its proper divisors (1).

994585981 is an equidigital number, since it uses as much as digits as its factorization.

994585981 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4665600, while the sum is 58.

The square root of 994585981 is about 31537.0572660164. The cubic root of 994585981 is about 998.1920603240.

The spelling of 994585981 in words is "nine hundred ninety-four million, five hundred eighty-five thousand, nine hundred eighty-one".