991099950 has 48 divisors (see below), whose sum is σ = 2459842560. Its totient is φ = 264087520.

The previous prime is 991099943. The next prime is 991099961. The reversal of 991099950 is 59990199.

It is a super-3 number, since 3×991099950³ (a number of 28 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a junction number, because it is equal to n+sod(n) for n = 991099893 and 991099902.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 367507 + ... + 370193.

It is an arithmetic number, because the mean of its divisors is an integer number (51246720).

Almost surely, 2^991099950 is an apocalyptic number.

991099950 is an abundant number, since it is smaller than the sum of its proper divisors (1468742610).

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

991099950 is a wasteful number, since it uses less digits than its factorization.

991099950 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5161 (or 5156 counting only the distinct ones).

The product of its (nonzero) digits is 295245, while the sum is 51.

The square root of 991099950 is about 31481.7399455621. The cubic root of 991099950 is about 997.0244716794.

The spelling of 991099950 in words is "nine hundred ninety-one million, ninety-nine thousand, nine hundred fifty".