999536640 has 96 divisors (see below), whose sum is σ = 3197834640. Its totient is φ = 266534912.

The previous prime is 999536633. The next prime is 999536647. The reversal of 999536640 is 46635999.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (999536633) and next prime (999536647).

It is a tau number, because it is divible by the number of its divisors (96).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (999536647) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14452 + ... + 46988.

Almost surely, 2^999536640 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 999536640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1598917320).

999536640 is an abundant number, since it is smaller than the sum of its proper divisors (2198298000).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

999536640 is a wasteful number, since it uses less digits than its factorization.

999536640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32567 (or 32547 counting only the distinct ones).

The product of its (nonzero) digits is 1574640, while the sum is 51.

The square root of 999536640 is about 31615.4493879179. The cubic root of 999536640 is about 999.8455228047.

The spelling of 999536640 in words is "nine hundred ninety-nine million, five hundred thirty-six thousand, six hundred forty".