991898000133 has 16 divisors (see below), whose sum is σ = 1344266044800. Its totient is φ = 650398524480.

The previous prime is 991898000131. The next prime is 991898000201. The reversal of 991898000133 is 331000898199.

It is a happy number.

It is not a de Polignac number, because 991898000133 - 2¹ = 991898000131 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (991898000131) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5079223 + ... + 5270891.

It is an arithmetic number, because the mean of its divisors is an integer number (84016627800).

Almost surely, 2^991898000133 is an apocalyptic number.

991898000133 is the 575007-th octagonal number.

It is an amenable number.

991898000133 is a deficient number, since it is larger than the sum of its proper divisors (352368044667).

991898000133 is a wasteful number, since it uses less digits than its factorization.

991898000133 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 220012.

The product of its (nonzero) digits is 419904, while the sum is 51.

The spelling of 991898000133 in words is "nine hundred ninety-one billion, eight hundred ninety-eight million, one hundred thirty-three", and thus it is an aban number.