999887641000 has 144 divisors (see below), whose sum is σ = 2370394589940. Its totient is φ = 394781860800.

The previous prime is 999887640977. The next prime is 999887641013. The reversal of 999887641000 is 146788999.

It is a powerful number, because all its prime factors have an exponent greater than 1 and also an Achilles number because it is not a perfect power.

It can be written as a sum of positive squares in 2 ways, for example, as 675924045316 + 323963595684 = 822146^2 + 569178^2 .

It is a nialpdrome in base 10.

It is a self number, because there is not a number n which added to its sum of digits gives 999887641000.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 3256962847 + ... + 3256963153.

Almost surely, 2^999887641000 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 999887641000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1185197294970).

999887641000 is an abundant number, since it is smaller than the sum of its proper divisors (1370506948940).

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

999887641000 is an equidigital number, since it uses as much as digits as its factorization.

999887641000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 841 (or 417 counting only the distinct ones).

The product of its (nonzero) digits is 7838208, while the sum is 61.

The spelling of 999887641000 in words is "nine hundred ninety-nine billion, eight hundred eighty-seven million, six hundred forty-one thousand".