991909010 has 8 divisors (see below), whose sum is σ = 1785436236. Its totient is φ = 396763600.

The previous prime is 991908991. The next prime is 991909021. The reversal of 991909010 is 10909199.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 967396609 + 24512401 = 31103^2 + 4951^2 .

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

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 49595441 + ... + 49595460.

Almost surely, 2^991909010 is an apocalyptic number.

991909010 is a deficient number, since it is larger than the sum of its proper divisors (793527226).

991909010 is a wasteful number, since it uses less digits than its factorization.

991909010 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 99190908.

The product of its (nonzero) digits is 6561, while the sum is 38.

The square root of 991909010 is about 31494.5869952282. The cubic root of 991909010 is about 997.2956966692.

The spelling of 991909010 in words is "nine hundred ninety-one million, nine hundred nine thousand, ten".