999040561 has 2 divisors, whose sum is σ = 999040562. Its totient is φ = 999040560.

The previous prime is 999040531. The next prime is 999040607. The reversal of 999040561 is 165040999.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 814759936 + 184280625 = 28544^2 + 13575^2 .

It is a cyclic number.

It is not a de Polignac number, because 999040561 - 2⁷ = 999040433 is a prime.

It is a super-3 number, since 3×999040561³ (a number of 28 digits) contains 333 as substring.

It is not a weakly prime, because it can be changed into another prime (999040531) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 499520280 + 499520281.

It is an arithmetic number, because the mean of its divisors is an integer number (499520281).

Almost surely, 2^999040561 is an apocalyptic number.

It is an amenable number.

999040561 is a deficient number, since it is larger than the sum of its proper divisors (1).

999040561 is an equidigital number, since it uses as much as digits as its factorization.

999040561 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 87480, while the sum is 43.

The square root of 999040561 is about 31607.6028986698. The cubic root of 999040561 is about 999.6800846651.

The spelling of 999040561 in words is "nine hundred ninety-nine million, forty thousand, five hundred sixty-one".