999505541 has 4 divisors (see below), whose sum is σ = 999671052. Its totient is φ = 999340032.

The previous prime is 999505519. The next prime is 999505543. The reversal of 999505541 is 145505999.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 145505999 = 5807 ⋅25057.

It can be written as a sum of positive squares in 2 ways, for example, as 875272225 + 124233316 = 29585^2 + 11146^2 .

It is a cyclic number.

It is not a de Polignac number, because 999505541 - 2⁶ = 999505477 is a prime.

It is a super-2 number, since 2×999505541² = 1998022652979405362, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (999505543) 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 3 ways as a sum of consecutive naturals, for example, 73340 + ... + 85893.

It is an arithmetic number, because the mean of its divisors is an integer number (249917763).

Almost surely, 2^999505541 is an apocalyptic number.

It is an amenable number.

999505541 is a deficient number, since it is larger than the sum of its proper divisors (165511).

999505541 is a wasteful number, since it uses less digits than its factorization.

999505541 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 165510.

The product of its (nonzero) digits is 364500, while the sum is 47.

The square root of 999505541 is about 31614.9575517665. The cubic root of 999505541 is about 999.8351531603.

The spelling of 999505541 in words is "nine hundred ninety-nine million, five hundred five thousand, five hundred forty-one".