991887814 has 8 divisors (see below), whose sum is σ = 1575351288. Its totient is φ = 466770720.

The previous prime is 991887779. The next prime is 991887829. The reversal of 991887814 is 418788199.

991887814 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a congruent 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, 14586552 + ... + 14586619.

It is an arithmetic number, because the mean of its divisors is an integer number (196918911).

Almost surely, 2^991887814 is an apocalyptic number.

991887814 is a deficient number, since it is larger than the sum of its proper divisors (583463474).

991887814 is a wasteful number, since it uses less digits than its factorization.

991887814 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29173190.

The product of its digits is 1161216, while the sum is 55.

The square root of 991887814 is about 31494.2504911611. The cubic root of 991887814 is about 997.2885929161.

The spelling of 991887814 in words is "nine hundred ninety-one million, eight hundred eighty-seven thousand, eight hundred fourteen".