9825399905891 has 8 divisors (see below), whose sum is σ = 10178963274624. Its totient is φ = 9474124973760.

The previous prime is 9825399905879. The next prime is 9825399905897. The reversal of 9825399905891 is 1985099935289.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 9825399905891 - 2²² = 9825395711587 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (9825399905897) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 572100410 + ... + 572117583.

It is an arithmetic number, because the mean of its divisors is an integer number (1272370409328).

Almost surely, 2^{9825399905891} is an apocalyptic number.

9825399905891 is a deficient number, since it is larger than the sum of its proper divisors (353563368733).

9825399905891 is a wasteful number, since it uses less digits than its factorization.

9825399905891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1144218301.

The product of its (nonzero) digits is 566870400, while the sum is 77.

The spelling of 9825399905891 in words is "nine trillion, eight hundred twenty-five billion, three hundred ninety-nine million, nine hundred five thousand, eight hundred ninety-one".