999609630431777 has 4 divisors (see below), whose sum is σ = 999609694968900. Its totient is φ = 999609565894656.

The previous prime is 999609630431729. The next prime is 999609630431833. The reversal of 999609630431777 is 777134036906999.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 241788069815296 + 757821560616481 = 15549536^2 + 27528559^2 .

It is a cyclic number.

It is not a de Polignac number, because 999609630431777 - 2¹⁴ = 999609630415393 is a prime.

It is a super-2 number, since 2×999609630431777² (a number of 31 digits) contains 22 as substring.

It is a deceptive number, since it divides R_{999609630431776}.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (999609630431717) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6453713 + ... + 45175985.

It is an arithmetic number, because the mean of its divisors is an integer number (249902423742225).

It is a Poulet number, since it divides 2^{999609630431776}-1.

Almost surely, 2^{999609630431777} is an apocalyptic number.

999609630431777 is the 25814849-th pentagonal number.

It is an amenable number.

999609630431777 is a deficient number, since it is larger than the sum of its proper divisors (64537123).

999609630431777 is a wasteful number, since it uses less digits than its factorization.

999609630431777 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 64537122.

The product of its (nonzero) digits is 2916548208, while the sum is 80.

The spelling of 999609630431777 in words is "nine hundred ninety-nine trillion, six hundred nine billion, six hundred thirty million, four hundred thirty-one thousand, seven hundred seventy-seven".